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-rw-r--r--gdb/ChangeLog10
-rw-r--r--gdb/Makefile.in10
-rw-r--r--gdb/config/mep/mep.mt3
-rw-r--r--gdb/configure.tgt2
-rw-r--r--gdb/mep-tdep.c2509
5 files changed, 2534 insertions, 0 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a1bdf89..cdcbdda 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,13 @@
+2007-02-23 Kevin Buettner <kevinb@redhat.com>
+
+ From Jim Blandy, Dave Brolley, Kevin Buettner, Don Howard, and
+ Richard Sandiford:
+ * Makefile.in (elf_mep_h, mep_desc_h, mep_opc_h): New variables.
+ (mep-tdep.o): New rule.
+ * configure.tgt (mep-*-*): New target.
+ * mep-tdep.c: New file.
+ * config/mep/mep.mt: New file.
+
2007-02-22 Markus Deuling <deuling@de.ibm.com>
* infrun.c (inferior_stop_reason, print_stop_reason): Remove
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 5047ffb..4b9f988 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -592,6 +592,7 @@ elf_arm_h = $(INCLUDE_DIR)/elf/arm.h $(elf_reloc_macros_h)
elf_bfd_h = $(BFD_SRC)/elf-bfd.h
elf_frv_h = $(INCLUDE_DIR)/elf/frv.h $(elf_reloc_macros_h)
elf_m32c_h = $(INCLUDE_DIR)/elf/m32c.h $(elf_reloc_macros_h)
+elf_mep_h = $(INCLUDE_DIR)/elf/mep.h $(elf_reloc_macros_h)
libaout_h = $(BFD_SRC)/libaout.h
libiberty_h = $(INCLUDE_DIR)/libiberty.h
libbfd_h = $(BFD_SRC)/libbfd.h
@@ -603,6 +604,8 @@ readline_h = $(READLINE_SRC)/readline.h
readline_tilde_h = $(READLINE_SRC)/tilde.h
readline_history_h = $(READLINE_SRC)/history.h
frv_desc_h = $(OPCODES_SRC)/frv-desc.h
+mep_desc_h = $(OPCODES_SRC)/mep-desc.h
+mep_opc_h = $(OPCODES_SRC)/mep-opc.h
sh_opc_h = $(OPCODES_SRC)/sh-opc.h
gdb_callback_h = $(INCLUDE_DIR)/gdb/callback.h
gdb_sim_arm_h = $(INCLUDE_DIR)/gdb/sim-arm.h
@@ -2357,6 +2360,13 @@ memattr.o: memattr.c $(defs_h) $(command_h) $(gdbcmd_h) $(memattr_h) \
$(target_h) $(value_h) $(language_h) $(vec_h) $(gdb_string_h)
mem-break.o: mem-break.c $(defs_h) $(symtab_h) $(breakpoint_h) $(inferior_h) \
$(target_h)
+mep-tdep.o: $(defs_h) $(frame_h) $(frame_unwind_h) $(frame_base_h) \
+ $(symtab_h) $(gdbtypes_h) $(gdbcmd_h) $(gdbcore_h) $(gdb_string_h) \
+ $(value_h) $(inferior_h) $(dis_asm_h) $(symfile_h) $(objfiles_h) \
+ $(language_h) $(arch_utils_h) $(regcache_h) $(remote_h) \
+ $(floatformat_h) $(sim_regno_h) $(disasm_h) $(trad_frame_h) \
+ $(reggroups_h) $(elf_bfd_h) $(elf_mep_h) $(gdb_assert_h) \
+ $(mep_desc_h) $(mep_opc_h) $(prologue_value_h) $(infcall_h)
mingw-hdep.o: mingw-hdep.c $(defs_h) $(serial_h) $(gdb_assert_h) \
$(gdb_select_h) $(gdb_string_h)
minsyms.o: minsyms.c $(defs_h) $(gdb_string_h) $(symtab_h) $(bfd_h) \
diff --git a/gdb/config/mep/mep.mt b/gdb/config/mep/mep.mt
new file mode 100644
index 0000000..584ec4b
--- /dev/null
+++ b/gdb/config/mep/mep.mt
@@ -0,0 +1,3 @@
+# Target: Toshiba Media Processor (MEP)
+TDEPFILES= mep-tdep.o prologue-value.o
+# No sim needed. Target uses SID.
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index 3682b46..94cd6bb 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -141,6 +141,8 @@ m68*-*-uclinux*) gdb_target=monitor ;;
m88*-*-openbsd*) gdb_target=obsd ;;
+mep-*-*) gdb_target=mep ;;
+
mips*-*-pe) gdb_target=wince ;;
mips*-sgi-irix5*) gdb_target=irix5 ;;
mips*-sgi-irix6*) gdb_target=irix6 ;;
diff --git a/gdb/mep-tdep.c b/gdb/mep-tdep.c
new file mode 100644
index 0000000..46c8310
--- /dev/null
+++ b/gdb/mep-tdep.c
@@ -0,0 +1,2509 @@
+/* Target-dependent code for the Toshiba MeP for GDB, the GNU debugger.
+
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ Free Software Foundation, Inc.
+
+ Contributed by Red Hat, Inc.
+
+ This file is part of GDB.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include "defs.h"
+#include "frame.h"
+#include "frame-unwind.h"
+#include "frame-base.h"
+#include "symtab.h"
+#include "gdbtypes.h"
+#include "gdbcmd.h"
+#include "gdbcore.h"
+#include "gdb_string.h"
+#include "value.h"
+#include "inferior.h"
+#include "dis-asm.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "language.h"
+#include "arch-utils.h"
+#include "regcache.h"
+#include "remote.h"
+#include "floatformat.h"
+#include "sim-regno.h"
+#include "disasm.h"
+#include "trad-frame.h"
+#include "reggroups.h"
+#include "elf-bfd.h"
+#include "elf/mep.h"
+#include "prologue-value.h"
+#include "opcode/cgen-bitset.h"
+#include "infcall.h"
+
+#include "gdb_assert.h"
+
+/* Get the user's customized MeP coprocessor register names from
+ libopcodes. */
+#include "opcodes/mep-desc.h"
+#include "opcodes/mep-opc.h"
+
+
+/* The gdbarch_tdep structure. */
+
+/* A quick recap for GDB hackers not familiar with the whole Toshiba
+ Media Processor story:
+
+ The MeP media engine is a configureable processor: users can design
+ their own coprocessors, implement custom instructions, adjust cache
+ sizes, select optional standard facilities like add-and-saturate
+ instructions, and so on. Then, they can build custom versions of
+ the GNU toolchain to support their customized chips. The
+ MeP-Integrator program (see utils/mep) takes a GNU toolchain source
+ tree, and a config file pointing to various files provided by the
+ user describing their customizations, and edits the source tree to
+ produce a compiler that can generate their custom instructions, an
+ assembler that can assemble them and recognize their custom
+ register names, and so on.
+
+ Furthermore, the user can actually specify several of these custom
+ configurations, called 'me_modules', and get a toolchain which can
+ produce code for any of them, given a compiler/assembler switch;
+ you say something like 'gcc -mconfig=mm_max' to generate code for
+ the me_module named 'mm_max'.
+
+ GDB, in particular, needs to:
+
+ - use the coprocessor control register names provided by the user
+ in their hardware description, in expressions, 'info register'
+ output, and disassembly,
+
+ - know the number, names, and types of the coprocessor's
+ general-purpose registers, adjust the 'info all-registers' output
+ accordingly, and print error messages if the user refers to one
+ that doesn't exist
+
+ - allow access to the control bus space only when the configuration
+ actually has a control bus, and recognize which regions of the
+ control bus space are actually populated,
+
+ - disassemble using the user's provided mnemonics for their custom
+ instructions, and
+
+ - recognize whether the $hi and $lo registers are present, and
+ allow access to them only when they are actually there.
+
+ There are three sources of information about what sort of me_module
+ we're actually dealing with:
+
+ - A MeP executable file indicates which me_module it was compiled
+ for, and libopcodes has tables describing each module. So, given
+ an executable file, we can find out about the processor it was
+ compiled for.
+
+ - There are SID command-line options to select a particular
+ me_module, overriding the one specified in the ELF file. SID
+ provides GDB with a fake read-only register, 'module', which
+ indicates which me_module GDB is communicating with an instance
+ of.
+
+ - There are SID command-line options to enable or disable certain
+ optional processor features, overriding the defaults for the
+ selected me_module. The MeP $OPT register indicates which
+ options are present on the current processor. */
+
+
+struct gdbarch_tdep
+{
+ /* A CGEN cpu descriptor for this BFD architecture and machine.
+
+ Note: this is *not* customized for any particular me_module; the
+ MeP libopcodes machinery actually puts off module-specific
+ customization until the last minute. So this contains
+ information about all supported me_modules. */
+ CGEN_CPU_DESC cpu_desc;
+
+ /* The me_module index from the ELF file we used to select this
+ architecture, or CONFIG_NONE if there was none.
+
+ Note that we should prefer to use the me_module number available
+ via the 'module' register, whenever we're actually talking to a
+ real target.
+
+ In the absence of live information, we'd like to get the
+ me_module number from the ELF file. But which ELF file: the
+ executable file, the core file, ... ? The answer is, "the last
+ ELF file we used to set the current architecture". Thus, we
+ create a separate instance of the gdbarch structure for each
+ me_module value mep_gdbarch_init sees, and store the me_module
+ value from the ELF file here. */
+ CONFIG_ATTR me_module;
+};
+
+
+
+/* Getting me_module information from the CGEN tables. */
+
+
+/* Find an entry in the DESC's hardware table whose name begins with
+ PREFIX, and whose ISA mask intersects COPRO_ISA_MASK, but does not
+ intersect with GENERIC_ISA_MASK. If there is no matching entry,
+ return zero. */
+static const CGEN_HW_ENTRY *
+find_hw_entry_by_prefix_and_isa (CGEN_CPU_DESC desc,
+ const char *prefix,
+ CGEN_BITSET *copro_isa_mask,
+ CGEN_BITSET *generic_isa_mask)
+{
+ int prefix_len = strlen (prefix);
+ int i;
+
+ for (i = 0; i < desc->hw_table.num_entries; i++)
+ {
+ const CGEN_HW_ENTRY *hw = desc->hw_table.entries[i];
+ if (strncmp (prefix, hw->name, prefix_len) == 0)
+ {
+ CGEN_BITSET *hw_isa_mask
+ = ((CGEN_BITSET *)
+ &CGEN_ATTR_CGEN_HW_ISA_VALUE (CGEN_HW_ATTRS (hw)));
+
+ if (cgen_bitset_intersect_p (hw_isa_mask, copro_isa_mask)
+ && ! cgen_bitset_intersect_p (hw_isa_mask, generic_isa_mask))
+ return hw;
+ }
+ }
+
+ return 0;
+}
+
+
+/* Find an entry in DESC's hardware table whose type is TYPE. Return
+ zero if there is none. */
+static const CGEN_HW_ENTRY *
+find_hw_entry_by_type (CGEN_CPU_DESC desc, CGEN_HW_TYPE type)
+{
+ int i;
+
+ for (i = 0; i < desc->hw_table.num_entries; i++)
+ {
+ const CGEN_HW_ENTRY *hw = desc->hw_table.entries[i];
+
+ if (hw->type == type)
+ return hw;
+ }
+
+ return 0;
+}
+
+
+/* Return the CGEN hardware table entry for the coprocessor register
+ set for ME_MODULE, whose name prefix is PREFIX. If ME_MODULE has
+ no such register set, return zero. If ME_MODULE is the generic
+ me_module CONFIG_NONE, return the table entry for the register set
+ whose hardware type is GENERIC_TYPE. */
+static const CGEN_HW_ENTRY *
+me_module_register_set (CONFIG_ATTR me_module,
+ const char *prefix,
+ CGEN_HW_TYPE generic_type)
+{
+ /* This is kind of tricky, because the hardware table is constructed
+ in a way that isn't very helpful. Perhaps we can fix that, but
+ here's how it works at the moment:
+
+ The configuration map, `mep_config_map', is indexed by me_module
+ number, and indicates which coprocessor and core ISAs that
+ me_module supports. The 'core_isa' mask includes all the core
+ ISAs, and the 'cop_isa' mask includes all the coprocessor ISAs.
+ The entry for the generic me_module, CONFIG_NONE, has an empty
+ 'cop_isa', and its 'core_isa' selects only the standard MeP
+ instruction set.
+
+ The CGEN CPU descriptor's hardware table, desc->hw_table, has
+ entries for all the register sets, for all me_modules. Each
+ entry has a mask indicating which ISAs use that register set.
+ So, if an me_module supports some coprocessor ISA, we can find
+ applicable register sets by scanning the hardware table for
+ register sets whose masks include (at least some of) those ISAs.
+
+ Each hardware table entry also has a name, whose prefix says
+ whether it's a general-purpose ("h-cr") or control ("h-ccr")
+ coprocessor register set. It might be nicer to have an attribute
+ indicating what sort of register set it was, that we could use
+ instead of pattern-matching on the name.
+
+ When there is no hardware table entry whose mask includes a
+ particular coprocessor ISA and whose name starts with a given
+ prefix, then that means that that coprocessor doesn't have any
+ registers of that type. In such cases, this function must return
+ a null pointer.
+
+ Coprocessor register sets' masks may or may not include the core
+ ISA for the me_module they belong to. Those generated by a2cgen
+ do, but the sample me_module included in the unconfigured tree,
+ 'ccfx', does not.
+
+ There are generic coprocessor register sets, intended only for
+ use with the generic me_module. Unfortunately, their masks
+ include *all* ISAs --- even those for coprocessors that don't
+ have such register sets. This makes detecting the case where a
+ coprocessor lacks a particular register set more complicated.
+
+ So, here's the approach we take:
+
+ - For CONFIG_NONE, we return the generic coprocessor register set.
+
+ - For any other me_module, we search for a register set whose
+ mask contains any of the me_module's coprocessor ISAs,
+ specifically excluding the generic coprocessor register sets. */
+
+ CGEN_CPU_DESC desc = gdbarch_tdep (current_gdbarch)->cpu_desc;
+ const CGEN_HW_ENTRY *hw;
+
+ if (me_module == CONFIG_NONE)
+ hw = find_hw_entry_by_type (desc, generic_type);
+ else
+ {
+ CGEN_BITSET *cop = &mep_config_map[me_module].cop_isa;
+ CGEN_BITSET *core = &mep_config_map[me_module].core_isa;
+ CGEN_BITSET *generic = &mep_config_map[CONFIG_NONE].core_isa;
+ CGEN_BITSET *cop_and_core;
+
+ /* The coprocessor ISAs include the ISA for the specific core which
+ has that coprocessor. */
+ cop_and_core = cgen_bitset_copy (cop);
+ cgen_bitset_union (cop, core, cop_and_core);
+ hw = find_hw_entry_by_prefix_and_isa (desc, prefix, cop_and_core, generic);
+ }
+
+ return hw;
+}
+
+
+/* Given a hardware table entry HW representing a register set, return
+ a pointer to the keyword table with all the register names. If HW
+ is NULL, return NULL, to propage the "no such register set" info
+ along. */
+static CGEN_KEYWORD *
+register_set_keyword_table (const CGEN_HW_ENTRY *hw)
+{
+ if (! hw)
+ return NULL;
+
+ /* Check that HW is actually a keyword table. */
+ gdb_assert (hw->asm_type == CGEN_ASM_KEYWORD);
+
+ /* The 'asm_data' field of a register set's hardware table entry
+ refers to a keyword table. */
+ return (CGEN_KEYWORD *) hw->asm_data;
+}
+
+
+/* Given a keyword table KEYWORD and a register number REGNUM, return
+ the name of the register, or "" if KEYWORD contains no register
+ whose number is REGNUM. */
+static char *
+register_name_from_keyword (CGEN_KEYWORD *keyword_table, int regnum)
+{
+ const CGEN_KEYWORD_ENTRY *entry
+ = cgen_keyword_lookup_value (keyword_table, regnum);
+
+ if (entry)
+ {
+ char *name = entry->name;
+
+ /* The CGEN keyword entries for register names include the
+ leading $, which appears in MeP assembly as well as in GDB.
+ But we don't want to return that; GDB core code adds that
+ itself. */
+ if (name[0] == '$')
+ name++;
+
+ return name;
+ }
+ else
+ return "";
+}
+
+
+/* Masks for option bits in the OPT special-purpose register. */
+enum {
+ MEP_OPT_DIV = 1 << 25, /* 32-bit divide instruction option */
+ MEP_OPT_MUL = 1 << 24, /* 32-bit multiply instruction option */
+ MEP_OPT_BIT = 1 << 23, /* bit manipulation instruction option */
+ MEP_OPT_SAT = 1 << 22, /* saturation instruction option */
+ MEP_OPT_CLP = 1 << 21, /* clip instruction option */
+ MEP_OPT_MIN = 1 << 20, /* min/max instruction option */
+ MEP_OPT_AVE = 1 << 19, /* average instruction option */
+ MEP_OPT_ABS = 1 << 18, /* absolute difference instruction option */
+ MEP_OPT_LDZ = 1 << 16, /* leading zero instruction option */
+ MEP_OPT_VL64 = 1 << 6, /* 64-bit VLIW operation mode option */
+ MEP_OPT_VL32 = 1 << 5, /* 32-bit VLIW operation mode option */
+ MEP_OPT_COP = 1 << 4, /* coprocessor option */
+ MEP_OPT_DSP = 1 << 2, /* DSP option */
+ MEP_OPT_UCI = 1 << 1, /* UCI option */
+ MEP_OPT_DBG = 1 << 0, /* DBG function option */
+};
+
+
+/* Given the option_mask value for a particular entry in
+ mep_config_map, produce the value the processor's OPT register
+ would use to represent the same set of options. */
+static unsigned int
+opt_from_option_mask (unsigned int option_mask)
+{
+ /* A table mapping OPT register bits onto CGEN config map option
+ bits. */
+ struct {
+ unsigned int opt_bit, option_mask_bit;
+ } bits[] = {
+ { MEP_OPT_DIV, 1 << CGEN_INSN_OPTIONAL_DIV_INSN },
+ { MEP_OPT_MUL, 1 << CGEN_INSN_OPTIONAL_MUL_INSN },
+ { MEP_OPT_DIV, 1 << CGEN_INSN_OPTIONAL_DIV_INSN },
+ { MEP_OPT_DBG, 1 << CGEN_INSN_OPTIONAL_DEBUG_INSN },
+ { MEP_OPT_LDZ, 1 << CGEN_INSN_OPTIONAL_LDZ_INSN },
+ { MEP_OPT_ABS, 1 << CGEN_INSN_OPTIONAL_ABS_INSN },
+ { MEP_OPT_AVE, 1 << CGEN_INSN_OPTIONAL_AVE_INSN },
+ { MEP_OPT_MIN, 1 << CGEN_INSN_OPTIONAL_MINMAX_INSN },
+ { MEP_OPT_CLP, 1 << CGEN_INSN_OPTIONAL_CLIP_INSN },
+ { MEP_OPT_SAT, 1 << CGEN_INSN_OPTIONAL_SAT_INSN },
+ { MEP_OPT_UCI, 1 << CGEN_INSN_OPTIONAL_UCI_INSN },
+ { MEP_OPT_DSP, 1 << CGEN_INSN_OPTIONAL_DSP_INSN },
+ { MEP_OPT_COP, 1 << CGEN_INSN_OPTIONAL_CP_INSN },
+ };
+
+ int i;
+ unsigned int opt = 0;
+
+ for (i = 0; i < (sizeof (bits) / sizeof (bits[0])); i++)
+ if (option_mask & bits[i].option_mask_bit)
+ opt |= bits[i].opt_bit;
+
+ return opt;
+}
+
+
+/* Return the value the $OPT register would use to represent the set
+ of options for ME_MODULE. */
+static unsigned int
+me_module_opt (CONFIG_ATTR me_module)
+{
+ return opt_from_option_mask (mep_config_map[me_module].option_mask);
+}
+
+
+/* Return the width of ME_MODULE's coprocessor data bus, in bits.
+ This is either 32 or 64. */
+static int
+me_module_cop_data_bus_width (CONFIG_ATTR me_module)
+{
+ if (mep_config_map[me_module].option_mask
+ & (1 << CGEN_INSN_OPTIONAL_CP64_INSN))
+ return 64;
+ else
+ return 32;
+}
+
+
+/* Return true if ME_MODULE is big-endian, false otherwise. */
+static int
+me_module_big_endian (CONFIG_ATTR me_module)
+{
+ return mep_config_map[me_module].big_endian;
+}
+
+
+/* Return the name of ME_MODULE, or NULL if it has no name. */
+static const char *
+me_module_name (CONFIG_ATTR me_module)
+{
+ /* The default me_module has "" as its name, but it's easier for our
+ callers to test for NULL. */
+ if (! mep_config_map[me_module].name
+ || mep_config_map[me_module].name[0] == '\0')
+ return NULL;
+ else
+ return mep_config_map[me_module].name;
+}
+
+/* Register set. */
+
+
+/* The MeP spec defines the following registers:
+ 16 general purpose registers (r0-r15)
+ 32 control/special registers (csr0-csr31)
+ 32 coprocessor general-purpose registers (c0 -- c31)
+ 64 coprocessor control registers (ccr0 -- ccr63)
+
+ For the raw registers, we assign numbers here explicitly, instead
+ of letting the enum assign them for us; the numbers are a matter of
+ external protocol, and shouldn't shift around as things are edited.
+
+ We access the control/special registers via pseudoregisters, to
+ enforce read-only portions that some registers have.
+
+ We access the coprocessor general purpose and control registers via
+ pseudoregisters, to make sure they appear in the proper order in
+ the 'info all-registers' command (which uses the register number
+ ordering), and also to allow them to be renamed and resized
+ depending on the me_module in use.
+
+ The MeP allows coprocessor general-purpose registers to be either
+ 32 or 64 bits long, depending on the configuration. Since we don't
+ want the format of the 'g' packet to vary from one core to another,
+ the raw coprocessor GPRs are always 64 bits. GDB doesn't allow the
+ types of registers to change (see the implementation of
+ register_type), so we have four banks of pseudoregisters for the
+ coprocessor gprs --- 32-bit vs. 64-bit, and integer
+ vs. floating-point --- and we show or hide them depending on the
+ configuration. */
+enum
+{
+ MEP_FIRST_RAW_REGNUM = 0,
+
+ MEP_FIRST_GPR_REGNUM = 0,
+ MEP_R0_REGNUM = 0,
+ MEP_R1_REGNUM = 1,
+ MEP_R2_REGNUM = 2,
+ MEP_R3_REGNUM = 3,
+ MEP_R4_REGNUM = 4,
+ MEP_R5_REGNUM = 5,
+ MEP_R6_REGNUM = 6,
+ MEP_R7_REGNUM = 7,
+ MEP_R8_REGNUM = 8,
+ MEP_R9_REGNUM = 9,
+ MEP_R10_REGNUM = 10,
+ MEP_R11_REGNUM = 11,
+ MEP_R12_REGNUM = 12,
+ MEP_FP_REGNUM = MEP_R8_REGNUM,
+ MEP_R13_REGNUM = 13,
+ MEP_TP_REGNUM = MEP_R13_REGNUM, /* (r13) Tiny data pointer */
+ MEP_R14_REGNUM = 14,
+ MEP_GP_REGNUM = MEP_R14_REGNUM, /* (r14) Global pointer */
+ MEP_R15_REGNUM = 15,
+ MEP_SP_REGNUM = MEP_R15_REGNUM, /* (r15) Stack pointer */
+ MEP_LAST_GPR_REGNUM = MEP_R15_REGNUM,
+
+ /* The raw control registers. These are the values as received via
+ the remote protocol, directly from the target; we only let user
+ code touch the via the pseudoregisters, which enforce read-only
+ bits. */
+ MEP_FIRST_RAW_CSR_REGNUM = 16,
+ MEP_RAW_PC_REGNUM = 16, /* Program counter */
+ MEP_RAW_LP_REGNUM = 17, /* Link pointer */
+ MEP_RAW_SAR_REGNUM = 18, /* Raw shift amount */
+ MEP_RAW_CSR3_REGNUM = 19, /* csr3: reserved */
+ MEP_RAW_RPB_REGNUM = 20, /* Raw repeat begin address */
+ MEP_RAW_RPE_REGNUM = 21, /* Repeat end address */
+ MEP_RAW_RPC_REGNUM = 22, /* Repeat count */
+ MEP_RAW_HI_REGNUM = 23, /* Upper 32 bits of result of 64 bit mult/div */
+ MEP_RAW_LO_REGNUM = 24, /* Lower 32 bits of result of 64 bit mult/div */
+ MEP_RAW_CSR9_REGNUM = 25, /* csr3: reserved */
+ MEP_RAW_CSR10_REGNUM = 26, /* csr3: reserved */
+ MEP_RAW_CSR11_REGNUM = 27, /* csr3: reserved */
+ MEP_RAW_MB0_REGNUM = 28, /* Raw modulo begin address 0 */
+ MEP_RAW_ME0_REGNUM = 29, /* Raw modulo end address 0 */
+ MEP_RAW_MB1_REGNUM = 30, /* Raw modulo begin address 1 */
+ MEP_RAW_ME1_REGNUM = 31, /* Raw modulo end address 1 */
+ MEP_RAW_PSW_REGNUM = 32, /* Raw program status word */
+ MEP_RAW_ID_REGNUM = 33, /* Raw processor ID/revision */
+ MEP_RAW_TMP_REGNUM = 34, /* Temporary */
+ MEP_RAW_EPC_REGNUM = 35, /* Exception program counter */
+ MEP_RAW_EXC_REGNUM = 36, /* Raw exception cause */
+ MEP_RAW_CFG_REGNUM = 37, /* Raw processor configuration*/
+ MEP_RAW_CSR22_REGNUM = 38, /* csr3: reserved */
+ MEP_RAW_NPC_REGNUM = 39, /* Nonmaskable interrupt PC */
+ MEP_RAW_DBG_REGNUM = 40, /* Raw debug */
+ MEP_RAW_DEPC_REGNUM = 41, /* Debug exception PC */
+ MEP_RAW_OPT_REGNUM = 42, /* Raw options */
+ MEP_RAW_RCFG_REGNUM = 43, /* Raw local ram config */
+ MEP_RAW_CCFG_REGNUM = 44, /* Raw cache config */
+ MEP_RAW_CSR29_REGNUM = 45, /* csr3: reserved */
+ MEP_RAW_CSR30_REGNUM = 46, /* csr3: reserved */
+ MEP_RAW_CSR31_REGNUM = 47, /* csr3: reserved */
+ MEP_LAST_RAW_CSR_REGNUM = MEP_RAW_CSR31_REGNUM,
+
+ /* The raw coprocessor general-purpose registers. These are all 64
+ bits wide. */
+ MEP_FIRST_RAW_CR_REGNUM = 48,
+ MEP_LAST_RAW_CR_REGNUM = MEP_FIRST_RAW_CR_REGNUM + 31,
+
+ MEP_FIRST_RAW_CCR_REGNUM = 80,
+ MEP_LAST_RAW_CCR_REGNUM = MEP_FIRST_RAW_CCR_REGNUM + 63,
+
+ /* The module number register. This is the index of the me_module
+ of which the current target is an instance. (This is not a real
+ MeP-specified register; it's provided by SID.) */
+ MEP_MODULE_REGNUM,
+
+ MEP_LAST_RAW_REGNUM = MEP_MODULE_REGNUM,
+
+ MEP_NUM_RAW_REGS = MEP_LAST_RAW_REGNUM + 1,
+
+ /* Pseudoregisters. See mep_pseudo_register_read and
+ mep_pseudo_register_write. */
+ MEP_FIRST_PSEUDO_REGNUM = MEP_NUM_RAW_REGS,
+
+ /* We have a pseudoregister for every control/special register, to
+ implement registers with read-only bits. */
+ MEP_FIRST_CSR_REGNUM = MEP_FIRST_PSEUDO_REGNUM,
+ MEP_PC_REGNUM = MEP_FIRST_CSR_REGNUM, /* Program counter */
+ MEP_LP_REGNUM, /* Link pointer */
+ MEP_SAR_REGNUM, /* shift amount */
+ MEP_CSR3_REGNUM, /* csr3: reserved */
+ MEP_RPB_REGNUM, /* repeat begin address */
+ MEP_RPE_REGNUM, /* Repeat end address */
+ MEP_RPC_REGNUM, /* Repeat count */
+ MEP_HI_REGNUM, /* Upper 32 bits of the result of 64 bit mult/div */
+ MEP_LO_REGNUM, /* Lower 32 bits of the result of 64 bit mult/div */
+ MEP_CSR9_REGNUM, /* csr3: reserved */
+ MEP_CSR10_REGNUM, /* csr3: reserved */
+ MEP_CSR11_REGNUM, /* csr3: reserved */
+ MEP_MB0_REGNUM, /* modulo begin address 0 */
+ MEP_ME0_REGNUM, /* modulo end address 0 */
+ MEP_MB1_REGNUM, /* modulo begin address 1 */
+ MEP_ME1_REGNUM, /* modulo end address 1 */
+ MEP_PSW_REGNUM, /* program status word */
+ MEP_ID_REGNUM, /* processor ID/revision */
+ MEP_TMP_REGNUM, /* Temporary */
+ MEP_EPC_REGNUM, /* Exception program counter */
+ MEP_EXC_REGNUM, /* exception cause */
+ MEP_CFG_REGNUM, /* processor configuration*/
+ MEP_CSR22_REGNUM, /* csr3: reserved */
+ MEP_NPC_REGNUM, /* Nonmaskable interrupt PC */
+ MEP_DBG_REGNUM, /* debug */
+ MEP_DEPC_REGNUM, /* Debug exception PC */
+ MEP_OPT_REGNUM, /* options */
+ MEP_RCFG_REGNUM, /* local ram config */
+ MEP_CCFG_REGNUM, /* cache config */
+ MEP_CSR29_REGNUM, /* csr3: reserved */
+ MEP_CSR30_REGNUM, /* csr3: reserved */
+ MEP_CSR31_REGNUM, /* csr3: reserved */
+ MEP_LAST_CSR_REGNUM = MEP_CSR31_REGNUM,
+
+ /* The 32-bit integer view of the coprocessor GPR's. */
+ MEP_FIRST_CR32_REGNUM,
+ MEP_LAST_CR32_REGNUM = MEP_FIRST_CR32_REGNUM + 31,
+
+ /* The 32-bit floating-point view of the coprocessor GPR's. */
+ MEP_FIRST_FP_CR32_REGNUM,
+ MEP_LAST_FP_CR32_REGNUM = MEP_FIRST_FP_CR32_REGNUM + 31,
+
+ /* The 64-bit integer view of the coprocessor GPR's. */
+ MEP_FIRST_CR64_REGNUM,
+ MEP_LAST_CR64_REGNUM = MEP_FIRST_CR64_REGNUM + 31,
+
+ /* The 64-bit floating-point view of the coprocessor GPR's. */
+ MEP_FIRST_FP_CR64_REGNUM,
+ MEP_LAST_FP_CR64_REGNUM = MEP_FIRST_FP_CR64_REGNUM + 31,
+
+ MEP_FIRST_CCR_REGNUM,
+ MEP_LAST_CCR_REGNUM = MEP_FIRST_CCR_REGNUM + 63,
+
+ MEP_LAST_PSEUDO_REGNUM = MEP_LAST_CCR_REGNUM,
+
+ MEP_NUM_PSEUDO_REGS = (MEP_LAST_PSEUDO_REGNUM - MEP_LAST_RAW_REGNUM),
+
+ MEP_NUM_REGS = MEP_NUM_RAW_REGS + MEP_NUM_PSEUDO_REGS
+};
+
+
+#define IN_SET(set, n) \
+ (MEP_FIRST_ ## set ## _REGNUM <= (n) && (n) <= MEP_LAST_ ## set ## _REGNUM)
+
+#define IS_GPR_REGNUM(n) (IN_SET (GPR, (n)))
+#define IS_RAW_CSR_REGNUM(n) (IN_SET (RAW_CSR, (n)))
+#define IS_RAW_CR_REGNUM(n) (IN_SET (RAW_CR, (n)))
+#define IS_RAW_CCR_REGNUM(n) (IN_SET (RAW_CCR, (n)))
+
+#define IS_CSR_REGNUM(n) (IN_SET (CSR, (n)))
+#define IS_CR32_REGNUM(n) (IN_SET (CR32, (n)))
+#define IS_FP_CR32_REGNUM(n) (IN_SET (FP_CR32, (n)))
+#define IS_CR64_REGNUM(n) (IN_SET (CR64, (n)))
+#define IS_FP_CR64_REGNUM(n) (IN_SET (FP_CR64, (n)))
+#define IS_CR_REGNUM(n) (IS_CR32_REGNUM (n) || IS_FP_CR32_REGNUM (n) \
+ || IS_CR64_REGNUM (n) || IS_FP_CR64_REGNUM (n))
+#define IS_CCR_REGNUM(n) (IN_SET (CCR, (n)))
+
+#define IS_RAW_REGNUM(n) (IN_SET (RAW, (n)))
+#define IS_PSEUDO_REGNUM(n) (IN_SET (PSEUDO, (n)))
+
+#define NUM_REGS_IN_SET(set) \
+ (MEP_LAST_ ## set ## _REGNUM - MEP_FIRST_ ## set ## _REGNUM + 1)
+
+#define MEP_GPR_SIZE (4) /* Size of a MeP general-purpose register. */
+#define MEP_PSW_SIZE (4) /* Size of the PSW register. */
+#define MEP_LP_SIZE (4) /* Size of the LP register. */
+
+
+/* Many of the control/special registers contain bits that cannot be
+ written to; some are entirely read-only. So we present them all as
+ pseudoregisters.
+
+ The following table describes the special properties of each CSR. */
+struct mep_csr_register
+{
+ /* The number of this CSR's raw register. */
+ int raw;
+
+ /* The number of this CSR's pseudoregister. */
+ int pseudo;
+
+ /* A mask of the bits that are writeable: if a bit is set here, then
+ it can be modified; if the bit is clear, then it cannot. */
+ LONGEST writeable_bits;
+};
+
+
+/* mep_csr_registers[i] describes the i'th CSR.
+ We just list the register numbers here explicitly to help catch
+ typos. */
+#define CSR(name) MEP_RAW_ ## name ## _REGNUM, MEP_ ## name ## _REGNUM
+struct mep_csr_register mep_csr_registers[] = {
+ { CSR(PC), 0xffffffff }, /* manual says r/o, but we can write it */
+ { CSR(LP), 0xffffffff },
+ { CSR(SAR), 0x0000003f },
+ { CSR(CSR3), 0xffffffff },
+ { CSR(RPB), 0xfffffffe },
+ { CSR(RPE), 0xffffffff },
+ { CSR(RPC), 0xffffffff },
+ { CSR(HI), 0xffffffff },
+ { CSR(LO), 0xffffffff },
+ { CSR(CSR9), 0xffffffff },
+ { CSR(CSR10), 0xffffffff },
+ { CSR(CSR11), 0xffffffff },
+ { CSR(MB0), 0x0000ffff },
+ { CSR(ME0), 0x0000ffff },
+ { CSR(MB1), 0x0000ffff },
+ { CSR(ME1), 0x0000ffff },
+ { CSR(PSW), 0x000003ff },
+ { CSR(ID), 0x00000000 },
+ { CSR(TMP), 0xffffffff },
+ { CSR(EPC), 0xffffffff },
+ { CSR(EXC), 0x000030f0 },
+ { CSR(CFG), 0x00c0001b },
+ { CSR(CSR22), 0xffffffff },
+ { CSR(NPC), 0xffffffff },
+ { CSR(DBG), 0x00000580 },
+ { CSR(DEPC), 0xffffffff },
+ { CSR(OPT), 0x00000000 },
+ { CSR(RCFG), 0x00000000 },
+ { CSR(CCFG), 0x00000000 },
+ { CSR(CSR29), 0xffffffff },
+ { CSR(CSR30), 0xffffffff },
+ { CSR(CSR31), 0xffffffff },
+};
+
+
+/* If R is the number of a raw register, then mep_raw_to_pseudo[R] is
+ the number of the corresponding pseudoregister. Otherwise,
+ mep_raw_to_pseudo[R] == R. */
+static int mep_raw_to_pseudo[MEP_NUM_REGS];
+
+/* If R is the number of a pseudoregister, then mep_pseudo_to_raw[R]
+ is the number of the underlying raw register. Otherwise
+ mep_pseudo_to_raw[R] == R. */
+static int mep_pseudo_to_raw[MEP_NUM_REGS];
+
+static void
+mep_init_pseudoregister_maps (void)
+{
+ int i;
+
+ /* Verify that mep_csr_registers covers all the CSRs, in order. */
+ gdb_assert (ARRAY_SIZE (mep_csr_registers) == NUM_REGS_IN_SET (CSR));
+ gdb_assert (ARRAY_SIZE (mep_csr_registers) == NUM_REGS_IN_SET (RAW_CSR));
+
+ /* Verify that the raw and pseudo ranges have matching sizes. */
+ gdb_assert (NUM_REGS_IN_SET (RAW_CSR) == NUM_REGS_IN_SET (CSR));
+ gdb_assert (NUM_REGS_IN_SET (RAW_CR) == NUM_REGS_IN_SET (CR32));
+ gdb_assert (NUM_REGS_IN_SET (RAW_CR) == NUM_REGS_IN_SET (CR64));
+ gdb_assert (NUM_REGS_IN_SET (RAW_CCR) == NUM_REGS_IN_SET (CCR));
+
+ for (i = 0; i < ARRAY_SIZE (mep_csr_registers); i++)
+ {
+ struct mep_csr_register *r = &mep_csr_registers[i];
+
+ gdb_assert (r->pseudo == MEP_FIRST_CSR_REGNUM + i);
+ gdb_assert (r->raw == MEP_FIRST_RAW_CSR_REGNUM + i);
+ }
+
+ /* Set up the initial raw<->pseudo mappings. */
+ for (i = 0; i < MEP_NUM_REGS; i++)
+ {
+ mep_raw_to_pseudo[i] = i;
+ mep_pseudo_to_raw[i] = i;
+ }
+
+ /* Add the CSR raw<->pseudo mappings. */
+ for (i = 0; i < ARRAY_SIZE (mep_csr_registers); i++)
+ {
+ struct mep_csr_register *r = &mep_csr_registers[i];
+
+ mep_raw_to_pseudo[r->raw] = r->pseudo;
+ mep_pseudo_to_raw[r->pseudo] = r->raw;
+ }
+
+ /* Add the CR raw<->pseudo mappings. */
+ for (i = 0; i < NUM_REGS_IN_SET (RAW_CR); i++)
+ {
+ int raw = MEP_FIRST_RAW_CR_REGNUM + i;
+ int pseudo32 = MEP_FIRST_CR32_REGNUM + i;
+ int pseudofp32 = MEP_FIRST_FP_CR32_REGNUM + i;
+ int pseudo64 = MEP_FIRST_CR64_REGNUM + i;
+ int pseudofp64 = MEP_FIRST_FP_CR64_REGNUM + i;
+
+ /* Truly, the raw->pseudo mapping depends on the current module.
+ But we use the raw->pseudo mapping when we read the debugging
+ info; at that point, we don't know what module we'll actually
+ be running yet. So, we always supply the 64-bit register
+ numbers; GDB knows how to pick a smaller value out of a
+ larger register properly. */
+ mep_raw_to_pseudo[raw] = pseudo64;
+ mep_pseudo_to_raw[pseudo32] = raw;
+ mep_pseudo_to_raw[pseudofp32] = raw;
+ mep_pseudo_to_raw[pseudo64] = raw;
+ mep_pseudo_to_raw[pseudofp64] = raw;
+ }
+
+ /* Add the CCR raw<->pseudo mappings. */
+ for (i = 0; i < NUM_REGS_IN_SET (CCR); i++)
+ {
+ int raw = MEP_FIRST_RAW_CCR_REGNUM + i;
+ int pseudo = MEP_FIRST_CCR_REGNUM + i;
+ mep_raw_to_pseudo[raw] = pseudo;
+ mep_pseudo_to_raw[pseudo] = raw;
+ }
+}
+
+
+static int
+mep_debug_reg_to_regnum (int debug_reg)
+{
+ /* The debug info uses the raw register numbers. */
+ return mep_raw_to_pseudo[debug_reg];
+}
+
+
+/* Return the size, in bits, of the coprocessor pseudoregister
+ numbered PSEUDO. */
+static int
+mep_pseudo_cr_size (int pseudo)
+{
+ if (IS_CR32_REGNUM (pseudo)
+ || IS_FP_CR32_REGNUM (pseudo))
+ return 32;
+ else if (IS_CR64_REGNUM (pseudo)
+ || IS_FP_CR64_REGNUM (pseudo))
+ return 64;
+ else
+ gdb_assert (0);
+}
+
+
+/* If the coprocessor pseudoregister numbered PSEUDO is a
+ floating-point register, return non-zero; if it is an integer
+ register, return zero. */
+static int
+mep_pseudo_cr_is_float (int pseudo)
+{
+ return (IS_FP_CR32_REGNUM (pseudo)
+ || IS_FP_CR64_REGNUM (pseudo));
+}
+
+
+/* Given a coprocessor GPR pseudoregister number, return its index
+ within that register bank. */
+static int
+mep_pseudo_cr_index (int pseudo)
+{
+ if (IS_CR32_REGNUM (pseudo))
+ return pseudo - MEP_FIRST_CR32_REGNUM;
+ else if (IS_FP_CR32_REGNUM (pseudo))
+ return pseudo - MEP_FIRST_FP_CR32_REGNUM;
+ else if (IS_CR64_REGNUM (pseudo))
+ return pseudo - MEP_FIRST_CR64_REGNUM;
+ else if (IS_FP_CR64_REGNUM (pseudo))
+ return pseudo - MEP_FIRST_FP_CR64_REGNUM;
+ else
+ gdb_assert (0);
+}
+
+
+/* Return the me_module index describing the current target.
+
+ If the current target has registers (e.g., simulator, remote
+ target), then this uses the value of the 'module' register, raw
+ register MEP_MODULE_REGNUM. Otherwise, this retrieves the value
+ from the ELF header's e_flags field of the current executable
+ file. */
+static CONFIG_ATTR
+current_me_module ()
+{
+ if (target_has_registers)
+ return read_register (MEP_MODULE_REGNUM);
+ else
+ return gdbarch_tdep (current_gdbarch)->me_module;
+}
+
+
+/* Return the set of options for the current target, in the form that
+ the OPT register would use.
+
+ If the current target has registers (e.g., simulator, remote
+ target), then this is the actual value of the OPT register. If the
+ current target does not have registers (e.g., an executable file),
+ then use the 'module_opt' field we computed when we build the
+ gdbarch object for this module. */
+static unsigned int
+current_options ()
+{
+ if (target_has_registers)
+ return read_register (MEP_OPT_REGNUM);
+ else
+ return me_module_opt (current_me_module ());
+}
+
+
+/* Return the width of the current me_module's coprocessor data bus,
+ in bits. This is either 32 or 64. */
+static int
+current_cop_data_bus_width ()
+{
+ return me_module_cop_data_bus_width (current_me_module ());
+}
+
+
+/* Return the keyword table of coprocessor general-purpose register
+ names appropriate for the me_module we're dealing with. */
+static CGEN_KEYWORD *
+current_cr_names ()
+{
+ const CGEN_HW_ENTRY *hw
+ = me_module_register_set (current_me_module (), "h-cr-", HW_H_CR);
+
+ return register_set_keyword_table (hw);
+}
+
+
+/* Return non-zero if the coprocessor general-purpose registers are
+ floating-point values, zero otherwise. */
+static int
+current_cr_is_float ()
+{
+ const CGEN_HW_ENTRY *hw
+ = me_module_register_set (current_me_module (), "h-cr-", HW_H_CR);
+
+ return CGEN_ATTR_CGEN_HW_IS_FLOAT_VALUE (CGEN_HW_ATTRS (hw));
+}
+
+
+/* Return the keyword table of coprocessor control register names
+ appropriate for the me_module we're dealing with. */
+static CGEN_KEYWORD *
+current_ccr_names ()
+{
+ const CGEN_HW_ENTRY *hw
+ = me_module_register_set (current_me_module (), "h-ccr-", HW_H_CCR);
+
+ return register_set_keyword_table (hw);
+}
+
+
+static const char *
+mep_register_name (int regnr)
+{
+ struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+
+ /* General-purpose registers. */
+ static const char *gpr_names[] = {
+ "r0", "r1", "r2", "r3", /* 0 */
+ "r4", "r5", "r6", "r7", /* 4 */
+ "fp", "r9", "r10", "r11", /* 8 */
+ "r12", "tp", "gp", "sp" /* 12 */
+ };
+
+ /* Special-purpose registers. */
+ static const char *csr_names[] = {
+ "pc", "lp", "sar", "", /* 0 csr3: reserved */
+ "rpb", "rpe", "rpc", "hi", /* 4 */
+ "lo", "", "", "", /* 8 csr9-csr11: reserved */
+ "mb0", "me0", "mb1", "me1", /* 12 */
+
+ "psw", "id", "tmp", "epc", /* 16 */
+ "exc", "cfg", "", "npc", /* 20 csr22: reserved */
+ "dbg", "depc", "opt", "rcfg", /* 24 */
+ "ccfg", "", "", "" /* 28 csr29-csr31: reserved */
+ };
+
+ if (IS_GPR_REGNUM (regnr))
+ return gpr_names[regnr - MEP_R0_REGNUM];
+ else if (IS_CSR_REGNUM (regnr))
+ {
+ /* The 'hi' and 'lo' registers are only present on processors
+ that have the 'MUL' or 'DIV' instructions enabled. */
+ if ((regnr == MEP_HI_REGNUM || regnr == MEP_LO_REGNUM)
+ && (! (current_options () & (MEP_OPT_MUL | MEP_OPT_DIV))))
+ return "";
+
+ return csr_names[regnr - MEP_FIRST_CSR_REGNUM];
+ }
+ else if (IS_CR_REGNUM (regnr))
+ {
+ CGEN_KEYWORD *names;
+ int cr_size;
+ int cr_is_float;
+
+ /* Does this module have a coprocessor at all? */
+ if (! (current_options () & MEP_OPT_COP))
+ return "";
+
+ names = current_cr_names ();
+ if (! names)
+ /* This module's coprocessor has no general-purpose registers. */
+ return "";
+
+ cr_size = current_cop_data_bus_width ();
+ if (cr_size != mep_pseudo_cr_size (regnr))
+ /* This module's coprocessor's GPR's are of a different size. */
+ return "";
+
+ cr_is_float = current_cr_is_float ();
+ /* The extra ! operators ensure we get boolean equality, not
+ numeric equality. */
+ if (! cr_is_float != ! mep_pseudo_cr_is_float (regnr))
+ /* This module's coprocessor's GPR's are of a different type. */
+ return "";
+
+ return register_name_from_keyword (names, mep_pseudo_cr_index (regnr));
+ }
+ else if (IS_CCR_REGNUM (regnr))
+ {
+ /* Does this module have a coprocessor at all? */
+ if (! (current_options () & MEP_OPT_COP))
+ return "";
+
+ {
+ CGEN_KEYWORD *names = current_ccr_names ();
+
+ if (! names)
+ /* This me_module's coprocessor has no control registers. */
+ return "";
+
+ return register_name_from_keyword (names, regnr-MEP_FIRST_CCR_REGNUM);
+ }
+ }
+
+ /* It might be nice to give the 'module' register a name, but that
+ would affect the output of 'info all-registers', which would
+ disturb the test suites. So we leave it invisible. */
+ else
+ return NULL;
+}
+
+
+/* Custom register groups for the MeP. */
+static struct reggroup *mep_csr_reggroup; /* control/special */
+static struct reggroup *mep_cr_reggroup; /* coprocessor general-purpose */
+static struct reggroup *mep_ccr_reggroup; /* coprocessor control */
+
+
+static int
+mep_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
+ struct reggroup *group)
+{
+ /* Filter reserved or unused register numbers. */
+ {
+ const char *name = mep_register_name (regnum);
+
+ if (! name || name[0] == '\0')
+ return 0;
+ }
+
+ /* We could separate the GPRs and the CSRs. Toshiba has approved of
+ the existing behavior, so we'd want to run that by them. */
+ if (group == general_reggroup)
+ return (IS_GPR_REGNUM (regnum)
+ || IS_CSR_REGNUM (regnum));
+
+ /* Everything is in the 'all' reggroup, except for the raw CSR's. */
+ else if (group == all_reggroup)
+ return (IS_GPR_REGNUM (regnum)
+ || IS_CSR_REGNUM (regnum)
+ || IS_CR_REGNUM (regnum)
+ || IS_CCR_REGNUM (regnum));
+
+ /* All registers should be saved and restored, except for the raw
+ CSR's.
+
+ This is probably right if the coprocessor is something like a
+ floating-point unit, but would be wrong if the coprocessor is
+ something that does I/O, where register accesses actually cause
+ externally-visible actions. But I get the impression that the
+ coprocessor isn't supposed to do things like that --- you'd use a
+ hardware engine, perhaps. */
+ else if (group == save_reggroup || group == restore_reggroup)
+ return (IS_GPR_REGNUM (regnum)
+ || IS_CSR_REGNUM (regnum)
+ || IS_CR_REGNUM (regnum)
+ || IS_CCR_REGNUM (regnum));
+
+ else if (group == mep_csr_reggroup)
+ return IS_CSR_REGNUM (regnum);
+ else if (group == mep_cr_reggroup)
+ return IS_CR_REGNUM (regnum);
+ else if (group == mep_ccr_reggroup)
+ return IS_CCR_REGNUM (regnum);
+ else
+ return 0;
+}
+
+
+static struct type *
+mep_register_type (struct gdbarch *gdbarch, int reg_nr)
+{
+ /* Coprocessor general-purpose registers may be either 32 or 64 bits
+ long. So for them, the raw registers are always 64 bits long (to
+ keep the 'g' packet format fixed), and the pseudoregisters vary
+ in length. */
+ if (IS_RAW_CR_REGNUM (reg_nr))
+ return builtin_type_uint64;
+
+ /* Since GDB doesn't allow registers to change type, we have two
+ banks of pseudoregisters for the coprocessor general-purpose
+ registers: one that gives a 32-bit view, and one that gives a
+ 64-bit view. We hide or show one or the other depending on the
+ current module. */
+ if (IS_CR_REGNUM (reg_nr))
+ {
+ int size = mep_pseudo_cr_size (reg_nr);
+ if (size == 32)
+ {
+ if (mep_pseudo_cr_is_float (reg_nr))
+ return builtin_type_float;
+ else
+ return builtin_type_uint32;
+ }
+ else if (size == 64)
+ {
+ if (mep_pseudo_cr_is_float (reg_nr))
+ return builtin_type_double;
+ else
+ return builtin_type_uint64;
+ }
+ else
+ gdb_assert (0);
+ }
+
+ /* All other registers are 32 bits long. */
+ else
+ return builtin_type_uint32;
+}
+
+
+static CORE_ADDR
+mep_read_pc (ptid_t ptid)
+{
+ ptid_t saved_ptid;
+ CORE_ADDR pc;
+
+ saved_ptid = inferior_ptid;
+ inferior_ptid = ptid;
+
+ pc = read_register (MEP_PC_REGNUM);
+
+ inferior_ptid = saved_ptid;
+ return pc;
+}
+
+static void
+mep_write_pc (CORE_ADDR pc, ptid_t ptid)
+{
+ ptid_t saved_ptid;
+
+ saved_ptid = inferior_ptid;
+ inferior_ptid = ptid;
+
+ write_register (MEP_PC_REGNUM, pc);
+
+ inferior_ptid = saved_ptid;
+}
+
+
+static void
+mep_pseudo_cr32_read (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int cookednum,
+ void *buf)
+{
+ /* Read the raw register into a 64-bit buffer, and then return the
+ appropriate end of that buffer. */
+ int rawnum = mep_pseudo_to_raw[cookednum];
+ char buf64[8];
+
+ gdb_assert (TYPE_LENGTH (register_type (gdbarch, rawnum)) == sizeof (buf64));
+ gdb_assert (TYPE_LENGTH (register_type (gdbarch, cookednum)) == 4);
+ regcache_raw_read (regcache, rawnum, buf64);
+ /* Slow, but legible. */
+ store_unsigned_integer (buf, 4, extract_unsigned_integer (buf64, 8));
+}
+
+
+static void
+mep_pseudo_cr64_read (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int cookednum,
+ void *buf)
+{
+ regcache_raw_read (regcache, mep_pseudo_to_raw[cookednum], buf);
+}
+
+
+static void
+mep_pseudo_register_read (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int cookednum,
+ gdb_byte *buf)
+{
+ if (IS_CSR_REGNUM (cookednum)
+ || IS_CCR_REGNUM (cookednum))
+ regcache_raw_read (regcache, mep_pseudo_to_raw[cookednum], buf);
+ else if (IS_CR32_REGNUM (cookednum)
+ || IS_FP_CR32_REGNUM (cookednum))
+ mep_pseudo_cr32_read (gdbarch, regcache, cookednum, buf);
+ else if (IS_CR64_REGNUM (cookednum)
+ || IS_FP_CR64_REGNUM (cookednum))
+ mep_pseudo_cr64_read (gdbarch, regcache, cookednum, buf);
+ else
+ gdb_assert (0);
+}
+
+
+static void
+mep_pseudo_csr_write (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int cookednum,
+ const void *buf)
+{
+ int size = register_size (gdbarch, cookednum);
+ struct mep_csr_register *r
+ = &mep_csr_registers[cookednum - MEP_FIRST_CSR_REGNUM];
+
+ if (r->writeable_bits == 0)
+ /* A completely read-only register; avoid the read-modify-
+ write cycle, and juts ignore the entire write. */
+ ;
+ else
+ {
+ /* A partially writeable register; do a read-modify-write cycle. */
+ ULONGEST old_bits;
+ ULONGEST new_bits;
+ ULONGEST mixed_bits;
+
+ regcache_raw_read_unsigned (regcache, r->raw, &old_bits);
+ new_bits = extract_unsigned_integer (buf, size);
+ mixed_bits = ((r->writeable_bits & new_bits)
+ | (~r->writeable_bits & old_bits));
+ regcache_raw_write_unsigned (regcache, r->raw, mixed_bits);
+ }
+}
+
+
+static void
+mep_pseudo_cr32_write (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int cookednum,
+ const void *buf)
+{
+ /* Expand the 32-bit value into a 64-bit value, and write that to
+ the pseudoregister. */
+ int rawnum = mep_pseudo_to_raw[cookednum];
+ char buf64[8];
+
+ gdb_assert (TYPE_LENGTH (register_type (gdbarch, rawnum)) == sizeof (buf64));
+ gdb_assert (TYPE_LENGTH (register_type (gdbarch, cookednum)) == 4);
+ /* Slow, but legible. */
+ store_unsigned_integer (buf64, 8, extract_unsigned_integer (buf, 4));
+ regcache_raw_write (regcache, rawnum, buf64);
+}
+
+
+static void
+mep_pseudo_cr64_write (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int cookednum,
+ const void *buf)
+{
+ regcache_raw_write (regcache, mep_pseudo_to_raw[cookednum], buf);
+}
+
+
+static void
+mep_pseudo_register_write (struct gdbarch *gdbarch,
+ struct regcache *regcache,
+ int cookednum,
+ const gdb_byte *buf)
+{
+ if (IS_CSR_REGNUM (cookednum))
+ mep_pseudo_csr_write (gdbarch, regcache, cookednum, buf);
+ else if (IS_CR32_REGNUM (cookednum)
+ || IS_FP_CR32_REGNUM (cookednum))
+ mep_pseudo_cr32_write (gdbarch, regcache, cookednum, buf);
+ else if (IS_CR64_REGNUM (cookednum)
+ || IS_FP_CR64_REGNUM (cookednum))
+ mep_pseudo_cr64_write (gdbarch, regcache, cookednum, buf);
+ else if (IS_CCR_REGNUM (cookednum))
+ regcache_raw_write (regcache, mep_pseudo_to_raw[cookednum], buf);
+ else
+ gdb_assert (0);
+}
+
+
+
+/* Disassembly. */
+
+/* The mep disassembler needs to know about the section in order to
+ work correctly. */
+int
+mep_gdb_print_insn (bfd_vma pc, disassemble_info * info)
+{
+ struct obj_section * s = find_pc_section (pc);
+
+ if (s)
+ {
+ /* The libopcodes disassembly code uses the section to find the
+ BFD, the BFD to find the ELF header, the ELF header to find
+ the me_module index, and the me_module index to select the
+ right instructions to print. */
+ info->section = s->the_bfd_section;
+ info->arch = bfd_arch_mep;
+
+ return print_insn_mep (pc, info);
+ }
+
+ return 0;
+}
+
+
+/* Prologue analysis. */
+
+
+/* The MeP has two classes of instructions: "core" instructions, which
+ are pretty normal RISC chip stuff, and "coprocessor" instructions,
+ which are mostly concerned with moving data in and out of
+ coprocessor registers, and branching on coprocessor condition
+ codes. There's space in the instruction set for custom coprocessor
+ instructions, too.
+
+ Instructions can be 16 or 32 bits long; the top two bits of the
+ first byte indicate the length. The coprocessor instructions are
+ mixed in with the core instructions, and there's no easy way to
+ distinguish them; you have to completely decode them to tell one
+ from the other.
+
+ The MeP also supports a "VLIW" operation mode, where instructions
+ always occur in fixed-width bundles. The bundles are either 32
+ bits or 64 bits long, depending on a fixed configuration flag. You
+ decode the first part of the bundle as normal; if it's a core
+ instruction, and there's any space left in the bundle, the
+ remainder of the bundle is a coprocessor instruction, which will
+ execute in parallel with the core instruction. If the first part
+ of the bundle is a coprocessor instruction, it occupies the entire
+ bundle.
+
+ So, here are all the cases:
+
+ - 32-bit VLIW mode:
+ Every bundle is four bytes long, and naturally aligned, and can hold
+ one or two instructions:
+ - 16-bit core instruction; 16-bit coprocessor instruction
+ These execute in parallel.
+ - 32-bit core instruction
+ - 32-bit coprocessor instruction
+
+ - 64-bit VLIW mode:
+ Every bundle is eight bytes long, and naturally aligned, and can hold
+ one or two instructions:
+ - 16-bit core instruction; 48-bit (!) coprocessor instruction
+ These execute in parallel.
+ - 32-bit core instruction; 32-bit coprocessor instruction
+ These execute in parallel.
+ - 64-bit coprocessor instruction
+
+ Now, the MeP manual doesn't define any 48- or 64-bit coprocessor
+ instruction, so I don't really know what's up there; perhaps these
+ are always the user-defined coprocessor instructions. */
+
+
+/* Return non-zero if PC is in a VLIW code section, zero
+ otherwise. */
+static int
+mep_pc_in_vliw_section (CORE_ADDR pc)
+{
+ struct obj_section *s = find_pc_section (pc);
+ if (s)
+ return (s->the_bfd_section->flags & SEC_MEP_VLIW);
+ return 0;
+}
+
+
+/* Set *INSN to the next core instruction at PC, and return the
+ address of the next instruction.
+
+ The MeP instruction encoding is endian-dependent. 16- and 32-bit
+ instructions are encoded as one or two two-byte parts, and each
+ part is byte-swapped independently. Thus:
+
+ void
+ foo (void)
+ {
+ asm ("movu $1, 0x123456");
+ asm ("sb $1,0x5678($2)");
+ asm ("clip $1, 19");
+ }
+
+ compiles to this big-endian code:
+
+ 0: d1 56 12 34 movu $1,0x123456
+ 4: c1 28 56 78 sb $1,22136($2)
+ 8: f1 01 10 98 clip $1,0x13
+ c: 70 02 ret
+
+ and this little-endian code:
+
+ 0: 56 d1 34 12 movu $1,0x123456
+ 4: 28 c1 78 56 sb $1,22136($2)
+ 8: 01 f1 98 10 clip $1,0x13
+ c: 02 70 ret
+
+ Instructions are returned in *INSN in an endian-independent form: a
+ given instruction always appears in *INSN the same way, regardless
+ of whether the instruction stream is big-endian or little-endian.
+
+ *INSN's most significant 16 bits are the first (i.e., at lower
+ addresses) 16 bit part of the instruction. Its least significant
+ 16 bits are the second (i.e., higher-addressed) 16 bit part of the
+ instruction, or zero for a 16-bit instruction. Both 16-bit parts
+ are fetched using the current endianness.
+
+ So, the *INSN values for the instruction sequence above would be
+ the following, in either endianness:
+
+ 0xd1561234 movu $1,0x123456
+ 0xc1285678 sb $1,22136($2)
+ 0xf1011098 clip $1,0x13
+ 0x70020000 ret
+
+ (In a sense, it would be more natural to return 16-bit instructions
+ in the least significant 16 bits of *INSN, but that would be
+ ambiguous. In order to tell whether you're looking at a 16- or a
+ 32-bit instruction, you have to consult the major opcode field ---
+ the most significant four bits of the instruction's first 16-bit
+ part. But if we put 16-bit instructions at the least significant
+ end of *INSN, then you don't know where to find the major opcode
+ field until you know if it's a 16- or a 32-bit instruction ---
+ which is where we started.)
+
+ If PC points to a core / coprocessor bundle in a VLIW section, set
+ *INSN to the core instruction, and return the address of the next
+ bundle. This has the effect of skipping the bundled coprocessor
+ instruction. That's okay, since coprocessor instructions aren't
+ significant to prologue analysis --- for the time being,
+ anyway. */
+
+static CORE_ADDR
+mep_get_insn (CORE_ADDR pc, long *insn)
+{
+ int pc_in_vliw_section;
+ int vliw_mode;
+ int insn_len;
+ char buf[2];
+
+ *insn = 0;
+
+ /* Are we in a VLIW section? */
+ pc_in_vliw_section = mep_pc_in_vliw_section (pc);
+ if (pc_in_vliw_section)
+ {
+ /* Yes, find out which bundle size. */
+ vliw_mode = current_options () & (MEP_OPT_VL32 | MEP_OPT_VL64);
+
+ /* If PC is in a VLIW section, but the current core doesn't say
+ that it supports either VLIW mode, then we don't have enough
+ information to parse the instruction stream it contains.
+ Since the "undifferentiated" standard core doesn't have
+ either VLIW mode bit set, this could happen.
+
+ But it shouldn't be an error to (say) set a breakpoint in a
+ VLIW section, if you know you'll never reach it. (Perhaps
+ you have a script that sets a bunch of standard breakpoints.)
+
+ So we'll just return zero here, and hope for the best. */
+ if (! (vliw_mode & (MEP_OPT_VL32 | MEP_OPT_VL64)))
+ return 0;
+
+ /* If both VL32 and VL64 are set, that's bogus, too. */
+ if (vliw_mode == (MEP_OPT_VL32 | MEP_OPT_VL64))
+ return 0;
+ }
+ else
+ vliw_mode = 0;
+
+ read_memory (pc, buf, sizeof (buf));
+ *insn = extract_unsigned_integer (buf, 2) << 16;
+
+ /* The major opcode --- the top four bits of the first 16-bit
+ part --- indicates whether this instruction is 16 or 32 bits
+ long. All 32-bit instructions have a major opcode whose top
+ two bits are 11; all the rest are 16-bit instructions. */
+ if ((*insn & 0xc0000000) == 0xc0000000)
+ {
+ /* Fetch the second 16-bit part of the instruction. */
+ read_memory (pc + 2, buf, sizeof (buf));
+ *insn = *insn | extract_unsigned_integer (buf, 2);
+ }
+
+ /* If we're in VLIW code, then the VLIW width determines the address
+ of the next instruction. */
+ if (vliw_mode)
+ {
+ /* In 32-bit VLIW code, all bundles are 32 bits long. We ignore the
+ coprocessor half of a core / copro bundle. */
+ if (vliw_mode == MEP_OPT_VL32)
+ insn_len = 4;
+
+ /* In 64-bit VLIW code, all bundles are 64 bits long. We ignore the
+ coprocessor half of a core / copro bundle. */
+ else if (vliw_mode == MEP_OPT_VL64)
+ insn_len = 8;
+
+ /* We'd better be in either core, 32-bit VLIW, or 64-bit VLIW mode. */
+ else
+ gdb_assert (0);
+ }
+
+ /* Otherwise, the top two bits of the major opcode are (again) what
+ we need to check. */
+ else if ((*insn & 0xc0000000) == 0xc0000000)
+ insn_len = 4;
+ else
+ insn_len = 2;
+
+ return pc + insn_len;
+}
+
+
+/* Sign-extend the LEN-bit value N. */
+#define SEXT(n, len) ((((int) (n)) ^ (1 << ((len) - 1))) - (1 << ((len) - 1)))
+
+/* Return the LEN-bit field at POS from I. */
+#define FIELD(i, pos, len) (((i) >> (pos)) & ((1 << (len)) - 1))
+
+/* Like FIELD, but sign-extend the field's value. */
+#define SFIELD(i, pos, len) (SEXT (FIELD ((i), (pos), (len)), (len)))
+
+
+/* Macros for decoding instructions.
+
+ Remember that 16-bit instructions are placed in bits 16..31 of i,
+ not at the least significant end; this means that the major opcode
+ field is always in the same place, regardless of the width of the
+ instruction. As a reminder of this, we show the lower 16 bits of a
+ 16-bit instruction as xxxx_xxxx_xxxx_xxxx. */
+
+/* SB Rn,(Rm) 0000_nnnn_mmmm_1000 */
+/* SH Rn,(Rm) 0000_nnnn_mmmm_1001 */
+/* SW Rn,(Rm) 0000_nnnn_mmmm_1010 */
+
+/* SW Rn,disp16(Rm) 1100_nnnn_mmmm_1010 dddd_dddd_dddd_dddd */
+#define IS_SW(i) (((i) & 0xf00f0000) == 0xc00a0000)
+/* SB Rn,disp16(Rm) 1100_nnnn_mmmm_1000 dddd_dddd_dddd_dddd */
+#define IS_SB(i) (((i) & 0xf00f0000) == 0xc0080000)
+/* SH Rn,disp16(Rm) 1100_nnnn_mmmm_1001 dddd_dddd_dddd_dddd */
+#define IS_SH(i) (((i) & 0xf00f0000) == 0xc0090000)
+#define SWBH_32_BASE(i) (FIELD (i, 20, 4))
+#define SWBH_32_SOURCE(i) (FIELD (i, 24, 4))
+#define SWBH_32_OFFSET(i) (SFIELD (i, 0, 16))
+
+/* SW Rn,disp7.align4(SP) 0100_nnnn_0ddd_dd10 xxxx_xxxx_xxxx_xxxx */
+#define IS_SW_IMMD(i) (((i) & 0xf0830000) == 0x40020000)
+#define SW_IMMD_SOURCE(i) (FIELD (i, 24, 4))
+#define SW_IMMD_OFFSET(i) (FIELD (i, 18, 5) << 2)
+
+/* SW Rn,(Rm) 0000_nnnn_mmmm_1010 xxxx_xxxx_xxxx_xxxx */
+#define IS_SW_REG(i) (((i) & 0xf00f0000) == 0x000a0000)
+#define SW_REG_SOURCE(i) (FIELD (i, 24, 4))
+#define SW_REG_BASE(i) (FIELD (i, 20, 4))
+
+/* ADD3 Rl,Rn,Rm 1001_nnnn_mmmm_llll xxxx_xxxx_xxxx_xxxx */
+#define IS_ADD3_16_REG(i) (((i) & 0xf0000000) == 0x90000000)
+#define ADD3_16_REG_SRC1(i) (FIELD (i, 20, 4)) /* n */
+#define ADD3_16_REG_SRC2(i) (FIELD (i, 24, 4)) /* m */
+
+/* ADD3 Rn,Rm,imm16 1100_nnnn_mmmm_0000 iiii_iiii_iiii_iiii */
+#define IS_ADD3_32(i) (((i) & 0xf00f0000) == 0xc0000000)
+#define ADD3_32_TARGET(i) (FIELD (i, 24, 4))
+#define ADD3_32_SOURCE(i) (FIELD (i, 20, 4))
+#define ADD3_32_OFFSET(i) (SFIELD (i, 0, 16))
+
+/* ADD3 Rn,SP,imm7.align4 0100_nnnn_0iii_ii00 xxxx_xxxx_xxxx_xxxx */
+#define IS_ADD3_16(i) (((i) & 0xf0830000) == 0x40000000)
+#define ADD3_16_TARGET(i) (FIELD (i, 24, 4))
+#define ADD3_16_OFFSET(i) (FIELD (i, 18, 5) << 2)
+
+/* ADD Rn,imm6 0110_nnnn_iiii_ii00 xxxx_xxxx_xxxx_xxxx */
+#define IS_ADD(i) (((i) & 0xf0030000) == 0x60000000)
+#define ADD_TARGET(i) (FIELD (i, 24, 4))
+#define ADD_OFFSET(i) (SFIELD (i, 18, 6))
+
+/* LDC Rn,imm5 0111_nnnn_iiii_101I xxxx_xxxx_xxxx_xxxx
+ imm5 = I||i[7:4] */
+#define IS_LDC(i) (((i) & 0xf00e0000) == 0x700a0000)
+#define LDC_IMM(i) ((FIELD (i, 16, 1) << 4) | FIELD (i, 20, 4))
+#define LDC_TARGET(i) (FIELD (i, 24, 4))
+
+/* LW Rn,disp16(Rm) 1100_nnnn_mmmm_1110 dddd_dddd_dddd_dddd */
+#define IS_LW(i) (((i) & 0xf00f0000) == 0xc00e0000)
+#define LW_TARGET(i) (FIELD (i, 24, 4))
+#define LW_BASE(i) (FIELD (i, 20, 4))
+#define LW_OFFSET(i) (SFIELD (i, 0, 16))
+
+/* MOV Rn,Rm 0000_nnnn_mmmm_0000 xxxx_xxxx_xxxx_xxxx */
+#define IS_MOV(i) (((i) & 0xf00f0000) == 0x00000000)
+#define MOV_TARGET(i) (FIELD (i, 24, 4))
+#define MOV_SOURCE(i) (FIELD (i, 20, 4))
+
+
+/* This structure holds the results of a prologue analysis. */
+struct mep_prologue
+{
+ /* The offset from the frame base to the stack pointer --- always
+ zero or negative.
+
+ Calling this a "size" is a bit misleading, but given that the
+ stack grows downwards, using offsets for everything keeps one
+ from going completely sign-crazy: you never change anything's
+ sign for an ADD instruction; always change the second operand's
+ sign for a SUB instruction; and everything takes care of
+ itself. */
+ int frame_size;
+
+ /* Non-zero if this function has initialized the frame pointer from
+ the stack pointer, zero otherwise. */
+ int has_frame_ptr;
+
+ /* If has_frame_ptr is non-zero, this is the offset from the frame
+ base to where the frame pointer points. This is always zero or
+ negative. */
+ int frame_ptr_offset;
+
+ /* The address of the first instruction at which the frame has been
+ set up and the arguments are where the debug info says they are
+ --- as best as we can tell. */
+ CORE_ADDR prologue_end;
+
+ /* reg_offset[R] is the offset from the CFA at which register R is
+ saved, or 1 if register R has not been saved. (Real values are
+ always zero or negative.) */
+ int reg_offset[MEP_NUM_REGS];
+};
+
+/* Return non-zero if VALUE is an incoming argument register. */
+
+static int
+is_arg_reg (pv_t value)
+{
+ return (value.kind == pvk_register
+ && MEP_R1_REGNUM <= value.reg && value.reg <= MEP_R4_REGNUM
+ && value.k == 0);
+}
+
+/* Return non-zero if a store of REG's current value VALUE to ADDR is
+ probably spilling an argument register to its stack slot in STACK.
+ Such instructions should be included in the prologue, if possible.
+
+ The store is a spill if:
+ - the value being stored is REG's original value;
+ - the value has not already been stored somewhere in STACK; and
+ - ADDR is a stack slot's address (e.g., relative to the original
+ value of the SP). */
+static int
+is_arg_spill (pv_t value, pv_t addr, struct pv_area *stack)
+{
+ return (is_arg_reg (value)
+ && pv_is_register (addr, MEP_SP_REGNUM)
+ && ! pv_area_find_reg (stack, current_gdbarch, value.reg, 0));
+}
+
+
+/* Function for finding saved registers in a 'struct pv_area'; we pass
+ this to pv_area_scan.
+
+ If VALUE is a saved register, ADDR says it was saved at a constant
+ offset from the frame base, and SIZE indicates that the whole
+ register was saved, record its offset in RESULT_UNTYPED. */
+static void
+check_for_saved (void *result_untyped, pv_t addr, CORE_ADDR size, pv_t value)
+{
+ struct mep_prologue *result = (struct mep_prologue *) result_untyped;
+
+ if (value.kind == pvk_register
+ && value.k == 0
+ && pv_is_register (addr, MEP_SP_REGNUM)
+ && size == register_size (current_gdbarch, value.reg))
+ result->reg_offset[value.reg] = addr.k;
+}
+
+
+/* Analyze a prologue starting at START_PC, going no further than
+ LIMIT_PC. Fill in RESULT as appropriate. */
+static void
+mep_analyze_prologue (CORE_ADDR start_pc, CORE_ADDR limit_pc,
+ struct mep_prologue *result)
+{
+ CORE_ADDR pc;
+ unsigned long insn;
+ int rn;
+ int found_lp = 0;
+ pv_t reg[MEP_NUM_REGS];
+ struct pv_area *stack;
+ struct cleanup *back_to;
+ CORE_ADDR after_last_frame_setup_insn = start_pc;
+
+ memset (result, 0, sizeof (*result));
+
+ for (rn = 0; rn < MEP_NUM_REGS; rn++)
+ {
+ reg[rn] = pv_register (rn, 0);
+ result->reg_offset[rn] = 1;
+ }
+
+ stack = make_pv_area (MEP_SP_REGNUM);
+ back_to = make_cleanup_free_pv_area (stack);
+
+ pc = start_pc;
+ while (pc < limit_pc)
+ {
+ CORE_ADDR next_pc;
+ pv_t pre_insn_fp, pre_insn_sp;
+
+ next_pc = mep_get_insn (pc, &insn);
+
+ /* A zero return from mep_get_insn means that either we weren't
+ able to read the instruction from memory, or that we don't
+ have enough information to be able to reliably decode it. So
+ we'll store here and hope for the best. */
+ if (! next_pc)
+ break;
+
+ /* Note the current values of the SP and FP, so we can tell if
+ this instruction changed them, below. */
+ pre_insn_fp = reg[MEP_FP_REGNUM];
+ pre_insn_sp = reg[MEP_SP_REGNUM];
+
+ if (IS_ADD (insn))
+ {
+ int rn = ADD_TARGET (insn);
+ CORE_ADDR imm6 = ADD_OFFSET (insn);
+
+ reg[rn] = pv_add_constant (reg[rn], imm6);
+ }
+ else if (IS_ADD3_16 (insn))
+ {
+ int rn = ADD3_16_TARGET (insn);
+ int imm7 = ADD3_16_OFFSET (insn);
+
+ reg[rn] = pv_add_constant (reg[MEP_SP_REGNUM], imm7);
+ }
+ else if (IS_ADD3_32 (insn))
+ {
+ int rn = ADD3_32_TARGET (insn);
+ int rm = ADD3_32_SOURCE (insn);
+ int imm16 = ADD3_32_OFFSET (insn);
+
+ reg[rn] = pv_add_constant (reg[rm], imm16);
+ }
+ else if (IS_SW_REG (insn))
+ {
+ int rn = SW_REG_SOURCE (insn);
+ int rm = SW_REG_BASE (insn);
+
+ /* If simulating this store would require us to forget
+ everything we know about the stack frame in the name of
+ accuracy, it would be better to just quit now. */
+ if (pv_area_store_would_trash (stack, reg[rm]))
+ break;
+
+ if (is_arg_spill (reg[rn], reg[rm], stack))
+ after_last_frame_setup_insn = next_pc;
+
+ pv_area_store (stack, reg[rm], 4, reg[rn]);
+ }
+ else if (IS_SW_IMMD (insn))
+ {
+ int rn = SW_IMMD_SOURCE (insn);
+ int offset = SW_IMMD_OFFSET (insn);
+ pv_t addr = pv_add_constant (reg[MEP_SP_REGNUM], offset);
+
+ /* If simulating this store would require us to forget
+ everything we know about the stack frame in the name of
+ accuracy, it would be better to just quit now. */
+ if (pv_area_store_would_trash (stack, addr))
+ break;
+
+ if (is_arg_spill (reg[rn], addr, stack))
+ after_last_frame_setup_insn = next_pc;
+
+ pv_area_store (stack, addr, 4, reg[rn]);
+ }
+ else if (IS_MOV (insn))
+ {
+ int rn = MOV_TARGET (insn);
+ int rm = MOV_SOURCE (insn);
+
+ reg[rn] = reg[rm];
+
+ if (pv_is_register (reg[rm], rm) && is_arg_reg (reg[rm]))
+ after_last_frame_setup_insn = next_pc;
+ }
+ else if (IS_SB (insn) || IS_SH (insn) || IS_SW (insn))
+ {
+ int rn = SWBH_32_SOURCE (insn);
+ int rm = SWBH_32_BASE (insn);
+ int disp = SWBH_32_OFFSET (insn);
+ int size = (IS_SB (insn) ? 1
+ : IS_SH (insn) ? 2
+ : IS_SW (insn) ? 4
+ : (gdb_assert (0), 1));
+ pv_t addr = pv_add_constant (reg[rm], disp);
+
+ if (pv_area_store_would_trash (stack, addr))
+ break;
+
+ if (is_arg_spill (reg[rn], addr, stack))
+ after_last_frame_setup_insn = next_pc;
+
+ pv_area_store (stack, addr, size, reg[rn]);
+ }
+ else if (IS_LDC (insn))
+ {
+ int rn = LDC_TARGET (insn);
+ int cr = LDC_IMM (insn) + MEP_FIRST_CSR_REGNUM;
+
+ reg[rn] = reg[cr];
+ }
+ else if (IS_LW (insn))
+ {
+ int rn = LW_TARGET (insn);
+ int rm = LW_BASE (insn);
+ int offset = LW_OFFSET (insn);
+ pv_t addr = pv_add_constant (reg[rm], offset);
+
+ reg[rn] = pv_area_fetch (stack, addr, 4);
+ }
+ else
+ /* We've hit some instruction we don't know how to simulate.
+ Strictly speaking, we should set every value we're
+ tracking to "unknown". But we'll be optimistic, assume
+ that we have enough information already, and stop
+ analysis here. */
+ break;
+
+ /* If this instruction changed the FP or decreased the SP (i.e.,
+ allocated more stack space), then this may be a good place to
+ declare the prologue finished. However, there are some
+ exceptions:
+
+ - If the instruction just changed the FP back to its original
+ value, then that's probably a restore instruction. The
+ prologue should definitely end before that.
+
+ - If the instruction increased the value of the SP (that is,
+ shrunk the frame), then it's probably part of a frame
+ teardown sequence, and the prologue should end before that. */
+
+ if (! pv_is_identical (reg[MEP_FP_REGNUM], pre_insn_fp))
+ {
+ if (! pv_is_register_k (reg[MEP_FP_REGNUM], MEP_FP_REGNUM, 0))
+ after_last_frame_setup_insn = next_pc;
+ }
+ else if (! pv_is_identical (reg[MEP_SP_REGNUM], pre_insn_sp))
+ {
+ /* The comparison of constants looks odd, there, because .k
+ is unsigned. All it really means is that the new value
+ is lower than it was before the instruction. */
+ if (pv_is_register (pre_insn_sp, MEP_SP_REGNUM)
+ && pv_is_register (reg[MEP_SP_REGNUM], MEP_SP_REGNUM)
+ && ((pre_insn_sp.k - reg[MEP_SP_REGNUM].k)
+ < (reg[MEP_SP_REGNUM].k - pre_insn_sp.k)))
+ after_last_frame_setup_insn = next_pc;
+ }
+
+ pc = next_pc;
+ }
+
+ /* Is the frame size (offset, really) a known constant? */
+ if (pv_is_register (reg[MEP_SP_REGNUM], MEP_SP_REGNUM))
+ result->frame_size = reg[MEP_SP_REGNUM].k;
+
+ /* Was the frame pointer initialized? */
+ if (pv_is_register (reg[MEP_FP_REGNUM], MEP_SP_REGNUM))
+ {
+ result->has_frame_ptr = 1;
+ result->frame_ptr_offset = reg[MEP_FP_REGNUM].k;
+ }
+
+ /* Record where all the registers were saved. */
+ pv_area_scan (stack, check_for_saved, (void *) result);
+
+ result->prologue_end = after_last_frame_setup_insn;
+
+ do_cleanups (back_to);
+}
+
+
+static CORE_ADDR
+mep_skip_prologue (CORE_ADDR pc)
+{
+ char *name;
+ CORE_ADDR func_addr, func_end;
+ struct mep_prologue p;
+
+ /* Try to find the extent of the function that contains PC. */
+ if (! find_pc_partial_function (pc, &name, &func_addr, &func_end))
+ return pc;
+
+ mep_analyze_prologue (pc, func_end, &p);
+ return p.prologue_end;
+}
+
+
+
+/* Breakpoints. */
+
+static const unsigned char *
+mep_breakpoint_from_pc (CORE_ADDR * pcptr, int *lenptr)
+{
+ static unsigned char breakpoint[] = { 0x70, 0x32 };
+ *lenptr = sizeof (breakpoint);
+ return breakpoint;
+}
+
+
+
+/* Frames and frame unwinding. */
+
+
+static struct mep_prologue *
+mep_analyze_frame_prologue (struct frame_info *next_frame,
+ void **this_prologue_cache)
+{
+ if (! *this_prologue_cache)
+ {
+ CORE_ADDR func_start, stop_addr;
+
+ *this_prologue_cache
+ = FRAME_OBSTACK_ZALLOC (struct mep_prologue);
+
+ func_start = frame_func_unwind (next_frame);
+ stop_addr = frame_pc_unwind (next_frame);
+
+ /* If we couldn't find any function containing the PC, then
+ just initialize the prologue cache, but don't do anything. */
+ if (! func_start)
+ stop_addr = func_start;
+
+ mep_analyze_prologue (func_start, stop_addr, *this_prologue_cache);
+ }
+
+ return *this_prologue_cache;
+}
+
+
+/* Given the next frame and a prologue cache, return this frame's
+ base. */
+static CORE_ADDR
+mep_frame_base (struct frame_info *next_frame,
+ void **this_prologue_cache)
+{
+ struct mep_prologue *p
+ = mep_analyze_frame_prologue (next_frame, this_prologue_cache);
+
+ /* In functions that use alloca, the distance between the stack
+ pointer and the frame base varies dynamically, so we can't use
+ the SP plus static information like prologue analysis to find the
+ frame base. However, such functions must have a frame pointer,
+ to be able to restore the SP on exit. So whenever we do have a
+ frame pointer, use that to find the base. */
+ if (p->has_frame_ptr)
+ {
+ CORE_ADDR fp
+ = frame_unwind_register_unsigned (next_frame, MEP_FP_REGNUM);
+ return fp - p->frame_ptr_offset;
+ }
+ else
+ {
+ CORE_ADDR sp
+ = frame_unwind_register_unsigned (next_frame, MEP_SP_REGNUM);
+ return sp - p->frame_size;
+ }
+}
+
+
+static void
+mep_frame_this_id (struct frame_info *next_frame,
+ void **this_prologue_cache,
+ struct frame_id *this_id)
+{
+ *this_id = frame_id_build (mep_frame_base (next_frame, this_prologue_cache),
+ frame_func_unwind (next_frame));
+}
+
+
+static void
+mep_frame_prev_register (struct frame_info *next_frame,
+ void **this_prologue_cache,
+ int regnum, int *optimizedp,
+ enum lval_type *lvalp, CORE_ADDR *addrp,
+ int *realnump, gdb_byte *bufferp)
+{
+ struct mep_prologue *p
+ = mep_analyze_frame_prologue (next_frame, this_prologue_cache);
+
+ /* There are a number of complications in unwinding registers on the
+ MeP, having to do with core functions calling VLIW functions and
+ vice versa.
+
+ The least significant bit of the link register, LP.LTOM, is the
+ VLIW mode toggle bit: it's set if a core function called a VLIW
+ function, or vice versa, and clear when the caller and callee
+ were both in the same mode.
+
+ So, if we're asked to unwind the PC, then we really want to
+ unwind the LP and clear the least significant bit. (Real return
+ addresses are always even.) And if we want to unwind the program
+ status word (PSW), we need to toggle PSW.OM if LP.LTOM is set.
+
+ Tweaking the register values we return in this way means that the
+ bits in BUFFERP[] are not the same as the bits you'd find at
+ ADDRP in the inferior, so we make sure lvalp is not_lval when we
+ do this. */
+ if (regnum == MEP_PC_REGNUM)
+ {
+ mep_frame_prev_register (next_frame, this_prologue_cache, MEP_LP_REGNUM,
+ optimizedp, lvalp, addrp, realnump, bufferp);
+ store_unsigned_integer (bufferp, MEP_LP_SIZE,
+ (extract_unsigned_integer (bufferp, MEP_LP_SIZE)
+ & ~1));
+ *lvalp = not_lval;
+ }
+ else
+ {
+ CORE_ADDR frame_base = mep_frame_base (next_frame, this_prologue_cache);
+ int reg_size = register_size (get_frame_arch (next_frame), regnum);
+
+ /* Our caller's SP is our frame base. */
+ if (regnum == MEP_SP_REGNUM)
+ {
+ *optimizedp = 0;
+ *lvalp = not_lval;
+ *addrp = 0;
+ *realnump = -1;
+ if (bufferp)
+ store_unsigned_integer (bufferp, reg_size, frame_base);
+ }
+
+ /* If prologue analysis says we saved this register somewhere,
+ return a description of the stack slot holding it. */
+ else if (p->reg_offset[regnum] != 1)
+ {
+ *optimizedp = 0;
+ *lvalp = lval_memory;
+ *addrp = frame_base + p->reg_offset[regnum];
+ *realnump = -1;
+ if (bufferp)
+ get_frame_memory (next_frame, *addrp, bufferp, reg_size);
+ }
+
+ /* Otherwise, presume we haven't changed the value of this
+ register, and get it from the next frame. */
+ else
+ frame_register_unwind (next_frame, regnum,
+ optimizedp, lvalp, addrp, realnump, bufferp);
+
+ /* If we need to toggle the operating mode, do so. */
+ if (regnum == MEP_PSW_REGNUM)
+ {
+ int lp_optimized;
+ enum lval_type lp_lval;
+ CORE_ADDR lp_addr;
+ int lp_realnum;
+ char lp_buffer[MEP_LP_SIZE];
+
+ /* Get the LP's value, too. */
+ frame_register_unwind (next_frame, MEP_LP_REGNUM,
+ &lp_optimized, &lp_lval, &lp_addr,
+ &lp_realnum, lp_buffer);
+
+ /* If LP.LTOM is set, then toggle PSW.OM. */
+ if (extract_unsigned_integer (lp_buffer, MEP_LP_SIZE) & 0x1)
+ store_unsigned_integer
+ (bufferp, MEP_PSW_SIZE,
+ (extract_unsigned_integer (bufferp, MEP_PSW_SIZE) ^ 0x1000));
+ *lvalp = not_lval;
+ }
+ }
+}
+
+
+static const struct frame_unwind mep_frame_unwind = {
+ NORMAL_FRAME,
+ mep_frame_this_id,
+ mep_frame_prev_register
+};
+
+
+static const struct frame_unwind *
+mep_frame_sniffer (struct frame_info *next_frame)
+{
+ return &mep_frame_unwind;
+}
+
+
+/* Our general unwinding function can handle unwinding the PC. */
+static CORE_ADDR
+mep_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_unwind_register_unsigned (next_frame, MEP_PC_REGNUM);
+}
+
+
+/* Our general unwinding function can handle unwinding the SP. */
+static CORE_ADDR
+mep_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_unwind_register_unsigned (next_frame, MEP_SP_REGNUM);
+}
+
+
+
+/* Return values. */
+
+
+static int
+mep_use_struct_convention (struct type *type)
+{
+ return (TYPE_LENGTH (type) > MEP_GPR_SIZE);
+}
+
+
+static void
+mep_extract_return_value (struct gdbarch *arch,
+ struct type *type,
+ struct regcache *regcache,
+ gdb_byte *valbuf)
+{
+ int byte_order = gdbarch_byte_order (arch);
+
+ /* Values that don't occupy a full register appear at the less
+ significant end of the value. This is the offset to where the
+ value starts. */
+ int offset;
+
+ /* Return values > MEP_GPR_SIZE bytes are returned in memory,
+ pointed to by R0. */
+ gdb_assert (TYPE_LENGTH (type) <= MEP_GPR_SIZE);
+
+ if (byte_order == BFD_ENDIAN_BIG)
+ offset = MEP_GPR_SIZE - TYPE_LENGTH (type);
+ else
+ offset = 0;
+
+ /* Return values that do fit in a single register are returned in R0. */
+ regcache_cooked_read_part (regcache, MEP_R0_REGNUM,
+ offset, TYPE_LENGTH (type),
+ valbuf);
+}
+
+
+static void
+mep_store_return_value (struct gdbarch *arch,
+ struct type *type,
+ struct regcache *regcache,
+ const gdb_byte *valbuf)
+{
+ int byte_order = gdbarch_byte_order (arch);
+
+ /* Values that fit in a single register go in R0. */
+ if (TYPE_LENGTH (type) <= MEP_GPR_SIZE)
+ {
+ /* Values that don't occupy a full register appear at the least
+ significant end of the value. This is the offset to where the
+ value starts. */
+ int offset;
+
+ if (byte_order == BFD_ENDIAN_BIG)
+ offset = MEP_GPR_SIZE - TYPE_LENGTH (type);
+ else
+ offset = 0;
+
+ regcache_cooked_write_part (regcache, MEP_R0_REGNUM,
+ offset, TYPE_LENGTH (type),
+ valbuf);
+ }
+
+ /* Return values larger than a single register are returned in
+ memory, pointed to by R0. Unfortunately, we can't count on R0
+ pointing to the return buffer, so we raise an error here. */
+ else
+ error ("GDB cannot set return values larger than four bytes; "
+ "the Media Processor's\n"
+ "calling conventions do not provide enough information "
+ "to do this.\n"
+ "Try using the 'return' command with no argument.");
+}
+
+enum return_value_convention
+mep_return_value (struct gdbarch *gdbarch, struct type *type,
+ struct regcache *regcache, gdb_byte *readbuf,
+ const gdb_byte *writebuf)
+{
+ if (mep_use_struct_convention (type))
+ {
+ if (readbuf)
+ {
+ ULONGEST addr;
+ /* Although the address of the struct buffer gets passed in R1, it's
+ returned in R0. Fetch R0's value and then read the memory
+ at that address. */
+ regcache_raw_read_unsigned (regcache, MEP_R0_REGNUM, &addr);
+ read_memory (addr, readbuf, TYPE_LENGTH (type));
+ }
+ if (writebuf)
+ {
+ /* Return values larger than a single register are returned in
+ memory, pointed to by R0. Unfortunately, we can't count on R0
+ pointing to the return buffer, so we raise an error here. */
+ error ("GDB cannot set return values larger than four bytes; "
+ "the Media Processor's\n"
+ "calling conventions do not provide enough information "
+ "to do this.\n"
+ "Try using the 'return' command with no argument.");
+ }
+ return RETURN_VALUE_ABI_RETURNS_ADDRESS;
+ }
+
+ if (readbuf)
+ mep_extract_return_value (gdbarch, type, regcache, readbuf);
+ if (writebuf)
+ mep_store_return_value (gdbarch, type, regcache, writebuf);
+
+ return RETURN_VALUE_REGISTER_CONVENTION;
+}
+
+
+/* Inferior calls. */
+
+
+static CORE_ADDR
+mep_frame_align (struct gdbarch *gdbarch, CORE_ADDR sp)
+{
+ /* Require word alignment. */
+ return sp & -4;
+}
+
+
+/* From "lang_spec2.txt":
+
+ 4.2 Calling conventions
+
+ 4.2.1 Core register conventions
+
+ - Parameters should be evaluated from left to right, and they
+ should be held in $1,$2,$3,$4 in order. The fifth parameter or
+ after should be held in the stack. If the size is larger than 4
+ bytes in the first four parameters, the pointer should be held in
+ the registers instead. If the size is larger than 4 bytes in the
+ fifth parameter or after, the pointer should be held in the stack.
+
+ - Return value of a function should be held in register $0. If the
+ size of return value is larger than 4 bytes, $1 should hold the
+ pointer pointing memory that would hold the return value. In this
+ case, the first parameter should be held in $2, the second one in
+ $3, and the third one in $4, and the forth parameter or after
+ should be held in the stack.
+
+ [This doesn't say so, but arguments shorter than four bytes are
+ passed in the least significant end of a four-byte word when
+ they're passed on the stack.] */
+
+
+/* Traverse the list of ARGC arguments ARGV; for every ARGV[i] too
+ large to fit in a register, save it on the stack, and place its
+ address in COPY[i]. SP is the initial stack pointer; return the
+ new stack pointer. */
+static CORE_ADDR
+push_large_arguments (CORE_ADDR sp, int argc, struct value **argv,
+ CORE_ADDR copy[])
+{
+ int i;
+
+ for (i = 0; i < argc; i++)
+ {
+ unsigned arg_len = TYPE_LENGTH (value_type (argv[i]));
+
+ if (arg_len > MEP_GPR_SIZE)
+ {
+ /* Reserve space for the copy, and then round the SP down, to
+ make sure it's all aligned properly. */
+ sp = (sp - arg_len) & -4;
+ write_memory (sp, value_contents (argv[i]), arg_len);
+ copy[i] = sp;
+ }
+ }
+
+ return sp;
+}
+
+
+static CORE_ADDR
+mep_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
+ struct regcache *regcache, CORE_ADDR bp_addr,
+ int argc, struct value **argv, CORE_ADDR sp,
+ int struct_return,
+ CORE_ADDR struct_addr)
+{
+ CORE_ADDR *copy = (CORE_ADDR *) alloca (argc * sizeof (copy[0]));
+ CORE_ADDR func_addr = find_function_addr (function, NULL);
+ int i;
+
+ /* The number of the next register available to hold an argument. */
+ int arg_reg;
+
+ /* The address of the next stack slot available to hold an argument. */
+ CORE_ADDR arg_stack;
+
+ /* The address of the end of the stack area for arguments. This is
+ just for error checking. */
+ CORE_ADDR arg_stack_end;
+
+ sp = push_large_arguments (sp, argc, argv, copy);
+
+ /* Reserve space for the stack arguments, if any. */
+ arg_stack_end = sp;
+ if (argc + (struct_addr ? 1 : 0) > 4)
+ sp -= ((argc + (struct_addr ? 1 : 0)) - 4) * MEP_GPR_SIZE;
+
+ arg_reg = MEP_R1_REGNUM;
+ arg_stack = sp;
+
+ /* If we're returning a structure by value, push the pointer to the
+ buffer as the first argument. */
+ if (struct_return)
+ {
+ regcache_cooked_write_unsigned (regcache, arg_reg, struct_addr);
+ arg_reg++;
+ }
+
+ for (i = 0; i < argc; i++)
+ {
+ unsigned arg_size = TYPE_LENGTH (value_type (argv[i]));
+ ULONGEST value;
+
+ /* Arguments that fit in a GPR get expanded to fill the GPR. */
+ if (arg_size <= MEP_GPR_SIZE)
+ value = extract_unsigned_integer (value_contents (argv[i]),
+ TYPE_LENGTH (value_type (argv[i])));
+
+ /* Arguments too large to fit in a GPR get copied to the stack,
+ and we pass a pointer to the copy. */
+ else
+ value = copy[i];
+
+ /* We use $1 -- $4 for passing arguments, then use the stack. */
+ if (arg_reg <= MEP_R4_REGNUM)
+ {
+ regcache_cooked_write_unsigned (regcache, arg_reg, value);
+ arg_reg++;
+ }
+ else
+ {
+ char buf[MEP_GPR_SIZE];
+ store_unsigned_integer (buf, MEP_GPR_SIZE, value);
+ write_memory (arg_stack, buf, MEP_GPR_SIZE);
+ arg_stack += MEP_GPR_SIZE;
+ }
+ }
+
+ gdb_assert (arg_stack <= arg_stack_end);
+
+ /* Set the return address. */
+ regcache_cooked_write_unsigned (regcache, MEP_LP_REGNUM, bp_addr);
+
+ /* Update the stack pointer. */
+ regcache_cooked_write_unsigned (regcache, MEP_SP_REGNUM, sp);
+
+ return sp;
+}
+
+
+static struct frame_id
+mep_unwind_dummy_id (struct gdbarch *gdbarch, struct frame_info *next_frame)
+{
+ return frame_id_build (mep_unwind_sp (gdbarch, next_frame),
+ frame_pc_unwind (next_frame));
+}
+
+
+
+/* Initialization. */
+
+
+static struct gdbarch *
+mep_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
+{
+ struct gdbarch *gdbarch;
+ struct gdbarch_tdep *tdep;
+
+ /* Which me_module are we building a gdbarch object for? */
+ CONFIG_ATTR me_module;
+
+ /* If we have a BFD in hand, figure out which me_module it was built
+ for. Otherwise, use the no-particular-me_module code. */
+ if (info.abfd)
+ {
+ /* The way to get the me_module code depends on the object file
+ format. At the moment, we only know how to handle ELF. */
+ if (bfd_get_flavour (info.abfd) == bfd_target_elf_flavour)
+ me_module = elf_elfheader (info.abfd)->e_flags & EF_MEP_INDEX_MASK;
+ else
+ me_module = CONFIG_NONE;
+ }
+ else
+ me_module = CONFIG_NONE;
+
+ /* If we're setting the architecture from a file, check the
+ endianness of the file against that of the me_module. */
+ if (info.abfd)
+ {
+ /* The negations on either side make the comparison treat all
+ non-zero (true) values as equal. */
+ if (! bfd_big_endian (info.abfd) != ! me_module_big_endian (me_module))
+ {
+ const char *module_name = me_module_name (me_module);
+ const char *module_endianness
+ = me_module_big_endian (me_module) ? "big" : "little";
+ const char *file_name = bfd_get_filename (info.abfd);
+ const char *file_endianness
+ = bfd_big_endian (info.abfd) ? "big" : "little";
+
+ fputc_unfiltered ('\n', gdb_stderr);
+ if (module_name)
+ warning ("the MeP module '%s' is %s-endian, but the executable\n"
+ "%s is %s-endian.",
+ module_name, module_endianness,
+ file_name, file_endianness);
+ else
+ warning ("the selected MeP module is %s-endian, but the "
+ "executable\n"
+ "%s is %s-endian.",
+ module_endianness, file_name, file_endianness);
+ }
+ }
+
+ /* Find a candidate among the list of architectures we've created
+ already. info->bfd_arch_info needs to match, but we also want
+ the right me_module: the ELF header's e_flags field needs to
+ match as well. */
+ for (arches = gdbarch_list_lookup_by_info (arches, &info);
+ arches != NULL;
+ arches = gdbarch_list_lookup_by_info (arches->next, &info))
+ if (gdbarch_tdep (arches->gdbarch)->me_module == me_module)
+ return arches->gdbarch;
+
+ tdep = (struct gdbarch_tdep *) xmalloc (sizeof (struct gdbarch_tdep));
+ gdbarch = gdbarch_alloc (&info, tdep);
+
+ /* Get a CGEN CPU descriptor for this architecture. */
+ {
+ const char *mach_name = info.bfd_arch_info->printable_name;
+ enum cgen_endian endian = (info.byte_order == BFD_ENDIAN_BIG
+ ? CGEN_ENDIAN_BIG
+ : CGEN_ENDIAN_LITTLE);
+
+ tdep->cpu_desc = mep_cgen_cpu_open (CGEN_CPU_OPEN_BFDMACH, mach_name,
+ CGEN_CPU_OPEN_ENDIAN, endian,
+ CGEN_CPU_OPEN_END);
+ }
+
+ tdep->me_module = me_module;
+
+ /* Register set. */
+ set_gdbarch_read_pc (gdbarch, mep_read_pc);
+ set_gdbarch_write_pc (gdbarch, mep_write_pc);
+ set_gdbarch_num_regs (gdbarch, MEP_NUM_RAW_REGS);
+ set_gdbarch_sp_regnum (gdbarch, MEP_SP_REGNUM);
+ set_gdbarch_register_name (gdbarch, mep_register_name);
+ set_gdbarch_register_type (gdbarch, mep_register_type);
+ set_gdbarch_num_pseudo_regs (gdbarch, MEP_NUM_PSEUDO_REGS);
+ set_gdbarch_pseudo_register_read (gdbarch, mep_pseudo_register_read);
+ set_gdbarch_pseudo_register_write (gdbarch, mep_pseudo_register_write);
+ set_gdbarch_dwarf2_reg_to_regnum (gdbarch, mep_debug_reg_to_regnum);
+ set_gdbarch_stab_reg_to_regnum (gdbarch, mep_debug_reg_to_regnum);
+
+ set_gdbarch_register_reggroup_p (gdbarch, mep_register_reggroup_p);
+ reggroup_add (gdbarch, all_reggroup);
+ reggroup_add (gdbarch, general_reggroup);
+ reggroup_add (gdbarch, save_reggroup);
+ reggroup_add (gdbarch, restore_reggroup);
+ reggroup_add (gdbarch, mep_csr_reggroup);
+ reggroup_add (gdbarch, mep_cr_reggroup);
+ reggroup_add (gdbarch, mep_ccr_reggroup);
+
+ /* Disassembly. */
+ set_gdbarch_print_insn (gdbarch, mep_gdb_print_insn);
+
+ /* Breakpoints. */
+ set_gdbarch_breakpoint_from_pc (gdbarch, mep_breakpoint_from_pc);
+ set_gdbarch_decr_pc_after_break (gdbarch, 0);
+ set_gdbarch_skip_prologue (gdbarch, mep_skip_prologue);
+
+ /* Frames and frame unwinding. */
+ frame_unwind_append_sniffer (gdbarch, mep_frame_sniffer);
+ set_gdbarch_unwind_pc (gdbarch, mep_unwind_pc);
+ set_gdbarch_unwind_sp (gdbarch, mep_unwind_sp);
+ set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
+ set_gdbarch_frame_args_skip (gdbarch, 0);
+
+ /* Return values. */
+ set_gdbarch_return_value (gdbarch, mep_return_value);
+
+ /* Inferior function calls. */
+ set_gdbarch_frame_align (gdbarch, mep_frame_align);
+ set_gdbarch_push_dummy_call (gdbarch, mep_push_dummy_call);
+ set_gdbarch_unwind_dummy_id (gdbarch, mep_unwind_dummy_id);
+
+ return gdbarch;
+}
+
+
+void
+_initialize_mep_tdep (void)
+{
+ mep_csr_reggroup = reggroup_new ("csr", USER_REGGROUP);
+ mep_cr_reggroup = reggroup_new ("cr", USER_REGGROUP);
+ mep_ccr_reggroup = reggroup_new ("ccr", USER_REGGROUP);
+
+ register_gdbarch_init (bfd_arch_mep, mep_gdbarch_init);
+
+ mep_init_pseudoregister_maps ();
+}