the "compile" command

This final patch adds the new "compile" command and subcommands, and
all the machinery needed to make it work.

A shared library supplied by gcc is used for all communications with
gcc.  Types and most aspects of symbols are provided directly by gdb
to the compiler using this library.

gdb provides some information about the user's code using plain text.
Macros are emitted this way, and DWARF location expressions (and
bounds for VLA) are compiled to C code.

This hybrid approach was taken because, on the one hand, it is better
to provide global declarations and such on demand; but on the other
hand, for local variables, translating DWARF location expressions to C
was much simpler than exporting a full compiler API to gdb -- the same
result, only easier to implement, understand, and debug.

In the ordinary mode, the user's expression is wrapped in a dummy
function.  After compilation, gdb inserts the resulting object code
into the inferior, then calls this function.

Access to local variables is provided by noting which registers are
used by location expressions, and passing a structure of register
values into the function.  Writes to registers are supported by
copying out these values after the function returns.

This approach was taken so that we could eventually implement other
more interesting features based on this same infrastructure; for
example, we're planning to investigate inferior-side breakpoint
conditions.

gdb/ChangeLog
2014-12-12  Phil Muldoon  <pmuldoon@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* NEWS: Update.
	* symtab.h (struct symbol_computed_ops) <generate_c_location>: New
	field.
	* p-lang.c (pascal_language_defn): Update.
	* opencl-lang.c (opencl_language_defn): Update.
	* objc-lang.c (objc_language_defn): Update.
	* m2-lang.c (m2_language_defn): Update.
	* language.h (struct language_defn) <la_get_compile_instance,
	la_compute_program>: New fields.
	* language.c (unknown_language_defn, auto_language_defn)
	(local_language_defn): Update.
	* jv-lang.c (java_language_defn): Update.
	* go-lang.c (go_language_defn): Update.
	* f-lang.c (f_language_defn): Update.
	* dwarf2loc.h (dwarf2_compile_property_to_c): Declare.
	* dwarf2loc.c (dwarf2_compile_property_to_c)
	(locexpr_generate_c_location, loclist_generate_c_location): New
	functions.
	(dwarf2_locexpr_funcs, dwarf2_loclist_funcs): Update.
	* defs.h (enum compile_i_scope_types): New.
	(enum command_control_type) <compile_control>: New constant.
	(struct command_line) <control_u>: New field.
	* d-lang.c (d_language_defn): Update.
	* compile/compile.c: New file.
	* compile/compile-c-support.c: New file.
	* compile/compile-c-symbols.c: New file.
	* compile/compile-c-types.c: New file.
	* compile/compile.h: New file.
	* compile/compile-internal.h: New file.
	* compile/compile-loc2c.c: New file.
	* compile/compile-object-load.c: New file.
	* compile/compile-object-load.h: New file.
	* compile/compile-object-run.c: New file.
	* compile/compile-object-run.h: New file.
	* cli/cli-script.c (multi_line_command_p, print_command_lines)
	(execute_control_command, process_next_line)
	(recurse_read_control_structure): Handle compile_control.
	* c-lang.h (c_get_compile_context, c_compute_program): Declare.
	* c-lang.c (c_language_defn, cplus_language_defn)
	(asm_language_defn, minimal_language_defn): Update.
	* ada-lang.c (ada_language_defn): Update.
	* Makefile.in (SUBDIR_GCC_COMPILE_OBS, SUBDIR_GCC_COMPILE_SRCS):
	New variables.
	(SFILES): Add SUBDIR_GCC_COMPILE_SRCS.
	(HFILES_NO_SRCDIR): Add compile.h.
	(COMMON_OBS): Add SUBDIR_GCC_COMPILE_OBS.
	(INIT_FILES): Add SUBDIR_GCC_COMPILE_SRCS.
	(compile.o, compile-c-types.o, compile-c-symbols.o)
	(compile-object-load.o, compile-object-run.o, compile-loc2c.o)
	(compile-c-support.o): New targets.

gdb/doc/ChangeLog
2014-12-12  Phil Muldoon  <pmuldoon@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.texinfo (Altering): Update.
	(Compiling and Injecting Code): New node.

gdb/testsuite/ChangeLog
2014-12-12  Phil Muldoon  <pmuldoon@redhat.com>
	    Jan Kratochvil  <jan.kratochvil@redhat.com>
	    Tom Tromey  <tromey@redhat.com>

	* configure.ac: Add gdb.compile/.
	* configure: Regenerate.
	* gdb.compile/Makefile.in: New file.
	* gdb.compile/compile-ops.exp: New file.
	* gdb.compile/compile-ops.c: New file.
	* gdb.compile/compile-tls.c: New file.
	* gdb.compile/compile-tls.exp: New file.
	* gdb.compile/compile-constvar.S: New file.
	* gdb.compile/compile-constvar.c: New file.
	* gdb.compile/compile-mod.c: New file.
	* gdb.compile/compile-nodebug.c: New file.
	* gdb.compile/compile-setjmp-mod.c: New file.
	* gdb.compile/compile-setjmp.c: New file.
	* gdb.compile/compile-setjmp.exp: New file.
	* gdb.compile/compile-shlib.c: New file.
	* gdb.compile/compile.c: New file.
	* gdb.compile/compile.exp: New file.
	* lib/gdb.exp (skip_compile_feature_tests): New proc.

1 files changed, 424 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.compile/compile-ops.exp b/gdb/testsuite/gdb.compile/compile-ops.exp
new file mode 100644
index 0000000..c295836
--- /dev/null
+++ b/gdb/testsuite/gdb.compile/compile-ops.exp
@@ -0,0 +1,424 @@
+# Copyright 2014 Free Software Foundation, Inc.
+
+# 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 3 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, see <http://www.gnu.org/licenses/>.
+
+# Some coverage testing of DWARF operators for the compiler
+# integration.
+
+load_lib dwarf.exp
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if {![dwarf2_support]} {
+    return 0
+}
+
+standard_testfile .c gdbjit-ops.S
+
+#
+# A port of the pr10770.c test code to the DWARF assembler format.
+#
+
+set assert_tos_non0 {
+    bra 3
+    skip -3
+}
+
+set assert_tos_0 [subst {
+    lit0
+    eq
+    $assert_tos_non0
+}]
+
+set program [subst {
+    lit0
+    nop
+    $assert_tos_0
+    lit1
+    const1u 1
+    eq
+    $assert_tos_non0
+    lit16
+    const2u 16
+    eq
+    $assert_tos_non0
+    lit31
+    const4u 31
+    ne
+    $assert_tos_0
+    lit1
+    neg
+    const1s -1
+    eq
+    $assert_tos_non0
+    lit16
+    neg
+    const2s -16
+    ne
+    $assert_tos_0
+    lit31
+    const4s -31
+    neg
+    ne
+    $assert_tos_0
+    lit7
+    dup
+    plus_uconst 2
+    lit9
+    eq
+    $assert_tos_non0
+    lit7
+    eq
+    $assert_tos_non0
+    lit20
+    lit1
+    drop
+    lit20
+    eq
+    $assert_tos_non0
+    lit17
+    lit19
+    over
+    lit17
+    eq
+    $assert_tos_non0
+    lit19
+    eq
+    $assert_tos_non0
+    lit17
+    eq
+    $assert_tos_non0
+    lit1
+    lit2
+    lit3
+    lit4
+    pick 2
+    lit2
+    eq
+    $assert_tos_non0
+    lit4
+    eq
+    $assert_tos_non0
+    lit3
+    eq
+    $assert_tos_non0
+    pick 0
+    lit2
+    eq
+    $assert_tos_non0
+    lit2
+    eq
+    $assert_tos_non0
+    lit1
+    eq
+    $assert_tos_non0
+    lit6
+    lit12
+    swap
+    lit6
+    eq
+    $assert_tos_non0
+    lit12
+    eq
+    $assert_tos_non0
+    lit7
+    lit8
+    lit9
+    rot
+    lit8
+    eq
+    $assert_tos_non0
+    lit7
+    eq
+    $assert_tos_non0
+    lit9
+    eq
+    $assert_tos_non0
+    lit7
+    abs
+    lit7
+    eq
+    $assert_tos_non0
+    const1s -123
+    abs
+    const1u 123
+    eq
+    $assert_tos_non0
+    lit3
+    lit6
+    and
+    lit2
+    eq
+    $assert_tos_non0
+    lit3
+    lit6
+    or
+    lit7
+    eq
+    $assert_tos_non0
+    lit17
+    lit2
+    minus
+    lit15
+    eq
+    $assert_tos_non0
+    # Divide is signed truncating toward zero.
+    const1s -6
+    const1s -2
+    div
+    lit3
+    eq
+    $assert_tos_non0
+    const1s -7
+    const1s 3
+    div
+    const1s -2
+    eq
+    $assert_tos_non0
+    # Modulo is unsigned.
+    const1s -6
+    const1s -4
+    mod
+    const1s -6
+    eq
+    $assert_tos_non0
+    const1s -6
+    lit4
+    mod
+    lit2
+    eq
+    $assert_tos_non0
+    lit6
+    const1s -4
+    mod
+    lit6
+    eq
+    $assert_tos_non0
+    # Signed modulo can be implemented using 'over over div mul minus'.
+    const1s -6
+    const1s -4
+    over
+    over
+    div
+    mul
+    minus
+    const1s -2
+    eq
+    $assert_tos_non0
+    const1s -7
+    lit3
+    over
+    over
+    div
+    mul
+    minus
+    const1s -1
+    eq
+    $assert_tos_non0
+    lit7
+    const1s -3
+    over
+    over
+    div
+    mul
+    minus
+    lit1
+    eq
+    $assert_tos_non0
+    lit16
+    lit31
+    plus_uconst 1
+    mul
+    const2u 512
+    eq
+    $assert_tos_non0
+    lit5
+    not
+    lit31
+    and
+    lit26
+    eq
+    $assert_tos_non0
+    lit12
+    lit31
+    plus
+    const1u 43
+    eq
+    $assert_tos_non0
+    const1s -6
+    lit2
+    plus
+    const1s -4
+    eq
+    $assert_tos_non0
+    const1s -6
+    plus_uconst 3
+    const1s -3
+    eq
+    $assert_tos_non0
+    lit16
+    lit4
+    shl
+    const2u 256
+    eq
+    $assert_tos_non0
+    lit16
+    lit3
+    shr
+    lit2
+    eq
+    $assert_tos_non0
+    const1s -16
+    lit3
+    shra
+    const1s -2
+    eq
+    $assert_tos_non0
+    lit3
+    lit6
+    xor
+    lit5
+    eq
+    $assert_tos_non0
+    lit3
+    lit6
+    le
+    $assert_tos_non0
+    lit3
+    lit3
+    le
+    $assert_tos_non0
+    lit6
+    lit3
+    le
+    $assert_tos_0
+    lit3
+    lit6
+    lt
+    $assert_tos_non0
+    lit3
+    lit3
+    lt
+    $assert_tos_0
+    lit6
+    lit3
+    lt
+    $assert_tos_0
+    lit3
+    lit6
+    ge
+    $assert_tos_0
+    lit3
+    lit3
+    ge
+    $assert_tos_non0
+    lit6
+    lit3
+    ge
+    $assert_tos_non0
+    lit3
+    lit6
+    gt
+    $assert_tos_0
+    lit3
+    lit3
+    gt
+    $assert_tos_0
+    lit6
+    lit3
+    gt
+    $assert_tos_non0
+    const1s -6
+    lit1
+    shr
+    lit0
+    gt
+    $assert_tos_non0
+    const1s -6
+    lit1
+    shra
+    lit0
+    lt
+    $assert_tos_non0
+    # Finally some result.
+    addr ptr
+}]
+
+# Make some DWARF for the test.
+set asm_file [standard_output_file $srcfile2]
+Dwarf::assemble $asm_file {
+    # Creating a CU with 4-byte addresses lets this test link on both
+    # 32- and 64-bit machines.
+    cu { addr_size 4 } {
+
+	declare_labels int_label
+	extern func_start func_end ptr
+
+	compile_unit {
+	    {name file1.txt}
+	    {language @DW_LANG_C}
+	    {low_pc func_start addr}
+	    {high_pc func_end addr}
+	} {
+	    global program
+
+	    int_label: base_type {
+		{name int}
+		{byte_size 4 sdata}
+		{encoding @DW_ATE_signed}
+	    }
+
+	    subprogram {
+		{external 1 flag}
+		{name func}
+		{low_pc func_start addr}
+		{high_pc func_end addr}
+	    } {
+		formal_parameter {
+		    {name param}
+		    {variable_parameter 1 flag}
+		    {type :$int_label}
+		    {location $program SPECIAL_expr}
+		}
+
+		formal_parameter {
+		    {name optimized_out}
+		    {variable_parameter 1 flag}
+		    {type :$int_label}
+		}
+	    }
+	}
+    }
+}
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} \
+	  [list $srcfile $asm_file] {nodebug}] } {
+    return -1
+}
+
+if ![runto func] {
+    return -1
+}
+
+if {[skip_compile_feature_tests]} {
+    untested "could not find libcc1 shared library"
+    return -1
+}
+
+# If we have a bug, this will hang.
+gdb_test_no_output "compile code param"
+
+# We can't access optimized-out variables, but their presence should
+# not affect compilations that don't refer to them.
+gdb_test "compile code optimized_out" \
+    ".*optimized out.*Compilation failed."