* Makefile.in (mips-linux-tdep.o): Update dependencies.

	* mips-tdep.c (mips_gdbarch_init): Move frame predicates
	to after osabi initialization.
	* mips-linux-tdep.c: Include "trad-frame.h" and "tramp-frame.h".
	(mips_linux_o32_sigframe_init, mips_linux_n32n64_sigframe_init): New
	functions.
	(mips_linux_o32_sigframe, mips_linux_o32_rt_sigframe)
	(mips_linux_n32_rt_sigframe, mips_linux_n64_rt_sigframe): New
	variables.
	(mips_linux_init_abi): Append signal trampoline unwinders.

1 files changed, 312 insertions, 0 deletions

diff --git a/gdb/mips-linux-tdep.c b/gdb/mips-linux-tdep.c
index 7e59eb1..48a82f7 100644
--- a/gdb/mips-linux-tdep.c
+++ b/gdb/mips-linux-tdep.c
@@ -28,6 +28,8 @@
 #include "gdb_string.h"
 #include "gdb_assert.h"
 #include "frame.h"
+#include "trad-frame.h"
+#include "tramp-frame.h"
 
 /* Copied from <asm/elf.h>.  */
 #define ELF_NGREG       45
@@ -797,6 +799,312 @@ mips_linux_skip_resolver (struct gdbarch *gdbarch, CORE_ADDR pc)
   return 0;
 }      
 
+/* Signal trampoline support.  There are four supported layouts for a
+   signal frame: o32 sigframe, o32 rt_sigframe, n32 rt_sigframe, and
+   n64 rt_sigframe.  We handle them all independently; not the most
+   efficient way, but simplest.  First, declare all the unwinders.  */
+
+static void mips_linux_o32_sigframe_init (const struct tramp_frame *self,
+					  struct frame_info *next_frame,
+					  struct trad_frame_cache *this_cache,
+					  CORE_ADDR func);
+
+static void mips_linux_n32n64_sigframe_init (const struct tramp_frame *self,
+					     struct frame_info *next_frame,
+					     struct trad_frame_cache *this_cache,
+					     CORE_ADDR func);
+
+#define MIPS_NR_LINUX 4000
+#define MIPS_NR_N64_LINUX 5000
+#define MIPS_NR_N32_LINUX 6000
+
+#define MIPS_NR_sigreturn MIPS_NR_LINUX + 119
+#define MIPS_NR_rt_sigreturn MIPS_NR_LINUX + 193
+#define MIPS_NR_N64_rt_sigreturn MIPS_NR_N64_LINUX + 211
+#define MIPS_NR_N32_rt_sigreturn MIPS_NR_N32_LINUX + 211
+
+#define MIPS_INST_LI_V0_SIGRETURN 0x24020000 + MIPS_NR_sigreturn
+#define MIPS_INST_LI_V0_RT_SIGRETURN 0x24020000 + MIPS_NR_rt_sigreturn
+#define MIPS_INST_LI_V0_N64_RT_SIGRETURN 0x24020000 + MIPS_NR_N64_rt_sigreturn
+#define MIPS_INST_LI_V0_N32_RT_SIGRETURN 0x24020000 + MIPS_NR_N32_rt_sigreturn
+#define MIPS_INST_SYSCALL 0x0000000c
+
+struct tramp_frame mips_linux_o32_sigframe = {
+  4,
+  { MIPS_INST_LI_V0_SIGRETURN, MIPS_INST_SYSCALL, TRAMP_SENTINEL_INSN },
+  mips_linux_o32_sigframe_init
+};
+
+struct tramp_frame mips_linux_o32_rt_sigframe = {
+  4,
+  { MIPS_INST_LI_V0_RT_SIGRETURN, MIPS_INST_SYSCALL, TRAMP_SENTINEL_INSN },
+  mips_linux_o32_sigframe_init
+};
+
+struct tramp_frame mips_linux_n32_rt_sigframe = {
+  4,
+  { MIPS_INST_LI_V0_N32_RT_SIGRETURN, MIPS_INST_SYSCALL, TRAMP_SENTINEL_INSN },
+  mips_linux_n32n64_sigframe_init
+};
+
+struct tramp_frame mips_linux_n64_rt_sigframe = {
+  4,
+  { MIPS_INST_LI_V0_N64_RT_SIGRETURN, MIPS_INST_SYSCALL, TRAMP_SENTINEL_INSN },
+  mips_linux_n32n64_sigframe_init
+};
+
+/* *INDENT-OFF* */
+/* The unwinder for o32 signal frames.  The legacy structures look
+   like this:
+
+   struct sigframe {
+     u32 sf_ass[4];            [argument save space for o32]
+     u32 sf_code[2];           [signal trampoline]
+     struct sigcontext sf_sc;
+     sigset_t sf_mask;
+   };
+
+   struct sigcontext {
+        unsigned int       sc_regmask;          [Unused]
+        unsigned int       sc_status;
+        unsigned long long sc_pc;
+        unsigned long long sc_regs[32];
+        unsigned long long sc_fpregs[32];
+        unsigned int       sc_ownedfp;
+        unsigned int       sc_fpc_csr;
+        unsigned int       sc_fpc_eir;          [Unused]
+        unsigned int       sc_used_math;
+        unsigned int       sc_ssflags;          [Unused]
+	[Alignment hole of four bytes]
+        unsigned long long sc_mdhi;
+        unsigned long long sc_mdlo;
+
+        unsigned int       sc_cause;            [Unused]
+        unsigned int       sc_badvaddr;         [Unused]
+
+        unsigned long      sc_sigset[4];        [kernel's sigset_t]
+   };
+
+   The RT signal frames look like this:
+
+   struct rt_sigframe {
+     u32 rs_ass[4];            [argument save space for o32]
+     u32 rs_code[2]            [signal trampoline]
+     struct siginfo rs_info;
+     struct ucontext rs_uc;
+   };
+
+   struct ucontext {
+     unsigned long     uc_flags;
+     struct ucontext  *uc_link;
+     stack_t           uc_stack;
+     [Alignment hole of four bytes]
+     struct sigcontext uc_mcontext;
+     sigset_t          uc_sigmask;
+   };  */
+/* *INDENT-ON* */
+
+#define SIGFRAME_CODE_OFFSET         (4 * 4)
+#define SIGFRAME_SIGCONTEXT_OFFSET   (6 * 4)
+
+#define RTSIGFRAME_SIGINFO_SIZE      128
+#define STACK_T_SIZE                 (3 * 4)
+#define UCONTEXT_SIGCONTEXT_OFFSET   (2 * 4 + STACK_T_SIZE + 4)
+#define RTSIGFRAME_SIGCONTEXT_OFFSET (SIGFRAME_SIGCONTEXT_OFFSET \
+				      + RTSIGFRAME_SIGINFO_SIZE \
+				      + UCONTEXT_SIGCONTEXT_OFFSET)
+
+#define SIGCONTEXT_PC       (1 * 8)
+#define SIGCONTEXT_REGS     (2 * 8)
+#define SIGCONTEXT_FPREGS   (34 * 8)
+#define SIGCONTEXT_FPCSR    (66 * 8 + 4)
+#define SIGCONTEXT_HI       (69 * 8)
+#define SIGCONTEXT_LO       (70 * 8)
+#define SIGCONTEXT_CAUSE    (71 * 8 + 0)
+#define SIGCONTEXT_BADVADDR (71 * 8 + 4)
+
+#define SIGCONTEXT_REG_SIZE 8
+
+static void
+mips_linux_o32_sigframe_init (const struct tramp_frame *self,
+			      struct frame_info *next_frame,
+			      struct trad_frame_cache *this_cache,
+			      CORE_ADDR func)
+{
+  int ireg, reg_position;
+  CORE_ADDR sigcontext_base = func - SIGFRAME_CODE_OFFSET;
+  const struct mips_regnum *regs = mips_regnum (current_gdbarch);
+
+  if (self == &mips_linux_o32_sigframe)
+    sigcontext_base += SIGFRAME_SIGCONTEXT_OFFSET;
+  else
+    sigcontext_base += RTSIGFRAME_SIGCONTEXT_OFFSET;
+    
+  /* I'm not proud of this hack.  Eventually we will have the infrastructure
+     to indicate the size of saved registers on a per-frame basis, but
+     right now we don't; the kernel saves eight bytes but we only want
+     four.  */
+  if (TARGET_BYTE_ORDER == BFD_ENDIAN_BIG)
+    sigcontext_base += 4;
+
+#if 0
+  trad_frame_set_reg_addr (this_cache, ORIG_ZERO_REGNUM + NUM_REGS,
+			   sigcontext_base + SIGCONTEXT_REGS);
+#endif
+
+  for (ireg = 1; ireg < 32; ireg++)
+    trad_frame_set_reg_addr (this_cache, ireg + ZERO_REGNUM + NUM_REGS,
+			     sigcontext_base + SIGCONTEXT_REGS
+			     + ireg * SIGCONTEXT_REG_SIZE);
+
+  for (ireg = 0; ireg < 32; ireg++)
+    trad_frame_set_reg_addr (this_cache, ireg + regs->fp0 + NUM_REGS,
+			     sigcontext_base + SIGCONTEXT_FPREGS
+			     + ireg * SIGCONTEXT_REG_SIZE);
+
+  trad_frame_set_reg_addr (this_cache, regs->pc + NUM_REGS,
+			   sigcontext_base + SIGCONTEXT_PC);
+
+  trad_frame_set_reg_addr (this_cache, regs->fp_control_status + NUM_REGS,
+			   sigcontext_base + SIGCONTEXT_FPCSR);
+  trad_frame_set_reg_addr (this_cache, regs->hi + NUM_REGS,
+			   sigcontext_base + SIGCONTEXT_HI);
+  trad_frame_set_reg_addr (this_cache, regs->lo + NUM_REGS,
+			   sigcontext_base + SIGCONTEXT_LO);
+  trad_frame_set_reg_addr (this_cache, regs->cause + NUM_REGS,
+			   sigcontext_base + SIGCONTEXT_CAUSE);
+  trad_frame_set_reg_addr (this_cache, regs->badvaddr + NUM_REGS,
+			   sigcontext_base + SIGCONTEXT_BADVADDR);
+
+  /* Choice of the bottom of the sigframe is somewhat arbitrary.  */
+  trad_frame_set_id (this_cache,
+		     frame_id_build (func - SIGFRAME_CODE_OFFSET, func));
+}
+
+/* *INDENT-OFF* */
+/* For N32/N64 things look different.  There is no non-rt signal frame.
+
+  struct rt_sigframe_n32 {
+    u32 rs_ass[4];                  [ argument save space for o32 ]
+    u32 rs_code[2];                 [ signal trampoline ]
+    struct siginfo rs_info;
+    struct ucontextn32 rs_uc;
+  };
+
+  struct ucontextn32 {
+    u32                 uc_flags;
+    s32                 uc_link;
+    stack32_t           uc_stack;
+    struct sigcontext   uc_mcontext;
+    sigset_t            uc_sigmask;   [ mask last for extensibility ]
+  };
+                                
+  struct rt_sigframe_n32 {
+    u32 rs_ass[4];                  [ argument save space for o32 ]
+    u32 rs_code[2];                 [ signal trampoline ]
+    struct siginfo rs_info;
+    struct ucontext rs_uc;
+  };
+
+  struct ucontext {
+    unsigned long     uc_flags;
+    struct ucontext  *uc_link;
+    stack_t           uc_stack;
+    struct sigcontext uc_mcontext;
+    sigset_t          uc_sigmask;   [ mask last for extensibility ]
+  };
+
+  And the sigcontext is different (this is for both n32 and n64):
+
+  struct sigcontext {
+    unsigned long long sc_regs[32];
+    unsigned long long sc_fpregs[32];
+    unsigned long long sc_mdhi;
+    unsigned long long sc_mdlo;
+    unsigned long long sc_pc;
+    unsigned int       sc_status;
+    unsigned int       sc_fpc_csr;
+    unsigned int       sc_fpc_eir;
+    unsigned int       sc_used_math;
+    unsigned int       sc_cause;
+    unsigned int       sc_badvaddr;
+  };  */
+/* *INDENT-ON* */
+
+#define N32_STACK_T_SIZE		STACK_T_SIZE
+#define N64_STACK_T_SIZE		(2 * 8 + 4)
+#define N32_UCONTEXT_SIGCONTEXT_OFFSET  (2 * 4 + N32_STACK_T_SIZE + 4)
+#define N64_UCONTEXT_SIGCONTEXT_OFFSET  (2 * 8 + N64_STACK_T_SIZE + 4)
+#define N32_SIGFRAME_SIGCONTEXT_OFFSET	(SIGFRAME_SIGCONTEXT_OFFSET \
+					 + RTSIGFRAME_SIGINFO_SIZE \
+					 + N32_UCONTEXT_SIGCONTEXT_OFFSET)
+#define N64_SIGFRAME_SIGCONTEXT_OFFSET	(SIGFRAME_SIGCONTEXT_OFFSET \
+					 + RTSIGFRAME_SIGINFO_SIZE \
+					 + N64_UCONTEXT_SIGCONTEXT_OFFSET)
+
+#define N64_SIGCONTEXT_REGS     (0 * 8)
+#define N64_SIGCONTEXT_FPREGS   (32 * 8)
+#define N64_SIGCONTEXT_HI       (64 * 8)
+#define N64_SIGCONTEXT_LO       (65 * 8)
+#define N64_SIGCONTEXT_PC       (66 * 8)
+#define N64_SIGCONTEXT_FPCSR    (67 * 8 + 1 * 4)
+#define N64_SIGCONTEXT_FIR      (67 * 8 + 2 * 4)
+#define N64_SIGCONTEXT_CAUSE    (67 * 8 + 4 * 4)
+#define N64_SIGCONTEXT_BADVADDR (67 * 8 + 5 * 4)
+
+#define N64_SIGCONTEXT_REG_SIZE 8
+  
+static void
+mips_linux_n32n64_sigframe_init (const struct tramp_frame *self,
+				 struct frame_info *next_frame,
+				 struct trad_frame_cache *this_cache,
+				 CORE_ADDR func)
+{
+  int ireg, reg_position;
+  CORE_ADDR sigcontext_base = func - SIGFRAME_CODE_OFFSET;
+  const struct mips_regnum *regs = mips_regnum (current_gdbarch);
+
+  if (self == &mips_linux_n32_rt_sigframe)
+    sigcontext_base += N32_SIGFRAME_SIGCONTEXT_OFFSET;
+  else
+    sigcontext_base += N64_SIGFRAME_SIGCONTEXT_OFFSET;
+    
+#if 0
+  trad_frame_set_reg_addr (this_cache, ORIG_ZERO_REGNUM + NUM_REGS,
+			   sigcontext_base + N64_SIGCONTEXT_REGS);
+#endif
+
+  for (ireg = 1; ireg < 32; ireg++)
+    trad_frame_set_reg_addr (this_cache, ireg + ZERO_REGNUM + NUM_REGS,
+			     sigcontext_base + N64_SIGCONTEXT_REGS
+			     + ireg * N64_SIGCONTEXT_REG_SIZE);
+
+  for (ireg = 0; ireg < 32; ireg++)
+    trad_frame_set_reg_addr (this_cache, ireg + regs->fp0 + NUM_REGS,
+			     sigcontext_base + N64_SIGCONTEXT_FPREGS
+			     + ireg * N64_SIGCONTEXT_REG_SIZE);
+
+  trad_frame_set_reg_addr (this_cache, regs->pc + NUM_REGS,
+			   sigcontext_base + N64_SIGCONTEXT_PC);
+
+  trad_frame_set_reg_addr (this_cache, regs->fp_control_status + NUM_REGS,
+			   sigcontext_base + N64_SIGCONTEXT_FPCSR);
+  trad_frame_set_reg_addr (this_cache, regs->hi + NUM_REGS,
+			   sigcontext_base + N64_SIGCONTEXT_HI);
+  trad_frame_set_reg_addr (this_cache, regs->lo + NUM_REGS,
+			   sigcontext_base + N64_SIGCONTEXT_LO);
+  trad_frame_set_reg_addr (this_cache, regs->cause + NUM_REGS,
+			   sigcontext_base + N64_SIGCONTEXT_CAUSE);
+  trad_frame_set_reg_addr (this_cache, regs->badvaddr + NUM_REGS,
+			   sigcontext_base + N64_SIGCONTEXT_BADVADDR);
+
+  /* Choice of the bottom of the sigframe is somewhat arbitrary.  */
+  trad_frame_set_id (this_cache,
+		     frame_id_build (func - SIGFRAME_CODE_OFFSET, func));
+}
+
+/* Initialize one of the GNU/Linux OS ABIs.  */
+
 static void
 mips_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 {
@@ -811,6 +1119,8 @@ mips_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 	set_solib_svr4_fetch_link_map_offsets
 	  (gdbarch, mips_linux_svr4_fetch_link_map_offsets);
 	set_mips_linux_register_addr (gdbarch, mips_linux_register_addr);
+	tramp_frame_append (gdbarch, &mips_linux_o32_sigframe);
+	tramp_frame_append (gdbarch, &mips_linux_o32_rt_sigframe);
 	break;
       case MIPS_ABI_N32:
 	set_gdbarch_get_longjmp_target (gdbarch,
@@ -818,6 +1128,7 @@ mips_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 	set_solib_svr4_fetch_link_map_offsets
 	  (gdbarch, mips_linux_svr4_fetch_link_map_offsets);
 	set_mips_linux_register_addr (gdbarch, mips64_linux_register_addr);
+	tramp_frame_append (gdbarch, &mips_linux_n32_rt_sigframe);
 	break;
       case MIPS_ABI_N64:
 	set_gdbarch_get_longjmp_target (gdbarch,
@@ -825,6 +1136,7 @@ mips_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 	set_solib_svr4_fetch_link_map_offsets
 	  (gdbarch, mips64_linux_svr4_fetch_link_map_offsets);
 	set_mips_linux_register_addr (gdbarch, mips64_linux_register_addr);
+	tramp_frame_append (gdbarch, &mips_linux_n64_rt_sigframe);
 	break;
       default:
 	internal_error (__FILE__, __LINE__, "can't handle ABI");