jit: add support for inline asm [PR87291]

This patch adds various entrypoints to libgccjit for directly embedding
asm statements into a compile, analogous to inline asm in the C frontend:
  gcc_jit_block_add_extended_asm
  gcc_jit_block_end_with_extended_asm_goto
  gcc_jit_extended_asm_as_object
  gcc_jit_extended_asm_set_volatile_flag
  gcc_jit_extended_asm_set_inline_flag
  gcc_jit_extended_asm_add_output_operand
  gcc_jit_extended_asm_add_input_operand
  gcc_jit_extended_asm_add_clobber
  gcc_jit_context_add_top_level_asm

gcc/jit/ChangeLog:
	PR jit/87291
	* docs/cp/topics/asm.rst: New file.
	* docs/cp/topics/index.rst (Topic Reference): Add it.
	* docs/topics/asm.rst: New file.
	* docs/topics/compatibility.rst (LIBGCCJIT_ABI_15): New.
	* docs/topics/functions.rst (Statements): Add link to extended
	asm.
	* docs/topics/index.rst (Topic Reference): Add asm.rst.
	* docs/topics/objects.rst: Add gcc_jit_extended_asm to ASCII art.
	* docs/_build/texinfo/Makefile: Regenerate.
	* docs/_build/texinfo/libgccjit.texi: Regenerate.
	* jit-common.h (gcc::jit::recording::extended_asm): New forward
	decl.
	(gcc::jit::recording::top_level_asm): Likewise.
	* jit-playback.c: Include "stmt.h".
	(build_string): New.
	(gcc::jit::playback::context::new_string_literal): Disambiguate
	build_string call.
	(gcc::jit::playback::context::add_top_level_asm): New.
	(build_operand_chain): New.
	(build_clobbers): New.
	(build_goto_operands): New.
	(gcc::jit::playback::block::add_extended_asm): New.
	* jit-playback.h (gcc::jit::playback::context::add_top_level_asm):
	New decl.
	(struct gcc::jit::playback::asm_operand): New struct.
	(gcc::jit::playback::block::add_extended_asm): New decl.
	* jit-recording.c (gcc::jit::recording::context::dump_to_file):
	Dump top-level asms.
	(gcc::jit::recording::context::add_top_level_asm): New.
	(gcc::jit::recording::block::add_extended_asm): New.
	(gcc::jit::recording::block::end_with_extended_asm_goto): New.
	(gcc::jit::recording::asm_operand::asm_operand): New.
	(gcc::jit::recording::asm_operand::print): New.
	(gcc::jit::recording::asm_operand::make_debug_string): New.
	(gcc::jit::recording::output_asm_operand::write_reproducer): New.
	(gcc::jit::recording::output_asm_operand::print): New.
	(gcc::jit::recording::input_asm_operand::write_reproducer): New.
	(gcc::jit::recording::input_asm_operand::print): New.
	(gcc::jit::recording::extended_asm::add_output_operand): New.
	(gcc::jit::recording::extended_asm::add_input_operand): New.
	(gcc::jit::recording::extended_asm::add_clobber): New.
	(gcc::jit::recording::extended_asm::replay_into): New.
	(gcc::jit::recording::extended_asm::make_debug_string): New.
	(gcc::jit::recording::extended_asm::write_flags): New.
	(gcc::jit::recording::extended_asm::write_clobbers): New.
	(gcc::jit::recording::extended_asm_simple::write_reproducer): New.
	(gcc::jit::recording::extended_asm::maybe_populate_playback_blocks):
	New.
	(gcc::jit::recording::extended_asm_goto::extended_asm_goto): New.
	(gcc::jit::recording::extended_asm_goto::replay_into): New.
	(gcc::jit::recording::extended_asm_goto::write_reproducer): New.
	(gcc::jit::recording::extended_asm_goto::get_successor_blocks):
	New.
	(gcc::jit::recording::extended_asm_goto::maybe_print_gotos): New.
	(gcc::jit::recording::extended_asm_goto::maybe_populate_playback_blocks):
	New.
	(gcc::jit::recording::top_level_asm::top_level_asm): New.
	(gcc::jit::recording::top_level_asm::replay_into): New.
	(gcc::jit::recording::top_level_asm::make_debug_string): New.
	(gcc::jit::recording::top_level_asm::write_to_dump): New.
	(gcc::jit::recording::top_level_asm::write_reproducer): New.
	* jit-recording.h
	(gcc::jit::recording::context::add_top_level_asm): New decl.
	(gcc::jit::recording::context::m_top_level_asms): New field.
	(gcc::jit::recording::block::add_extended_asm): New decl.
	(gcc::jit::recording::block::end_with_extended_asm_goto): New
	decl.
	(gcc::jit::recording::asm_operand): New class.
	(gcc::jit::recording::output_asm_operand): New class.
	(gcc::jit::recording::input_asm_operand): New class.
	(gcc::jit::recording::extended_asm): New class.
	(gcc::jit::recording::extended_asm_simple): New class.
	(gcc::jit::recording::extended_asm_goto): New class.
	(gcc::jit::recording::top_level_asm): New class.
	* libgccjit++.h (gccjit::extended_asm): New forward decl.
	(gccjit::context::add_top_level_asm): New.
	(gccjit::block::add_extended_asm): New.
	(gccjit::block::end_with_extended_asm_goto): New.
	(gccjit::extended_asm): New class.
	(gccjit::extended_asm::extended_asm): New ctors.
	(gccjit::extended_asm::set_volatile_flag): New.
	(gccjit::extended_asm::set_inline_flag): New.
	(gccjit::extended_asm::add_output_operand): New.
	(gccjit::extended_asm::add_input_operand): New.
	(gccjit::extended_asm::add_clobber): New.
	(gccjit::extended_asm::get_inner_extended_asm): New.
	* libgccjit.c (struct gcc_jit_extended_asm): New.
	(jit_error): Make "loc" param take a gcc::jit::recording::location *
	rather than a gcc_jit_location *.
	(gcc_jit_block_add_extended_asm): New entrypoint.
	(gcc_jit_block_end_with_extended_asm_goto): New entrypoint.
	(gcc_jit_extended_asm_as_object): New entrypoint.
	(gcc_jit_extended_asm_set_volatile_flag): New entrypoint.
	(gcc_jit_extended_asm_set_inline_flag): New entrypoint.
	(gcc_jit_extended_asm_add_output_operand): New entrypoint.
	(gcc_jit_extended_asm_add_clobber): New entrypoint.
	(gcc_jit_context_add_top_level_asm): New entrypoint.
	* libgccjit.h: Add gcc_jit_extended_asm to ASCII art.
	(gcc_jit_extended_asm): New typedef.
	(LIBGCCJIT_HAVE_ASM_STATEMENTS): New define.
	(gcc_jit_block_add_extended_asm): New entrypoint.
	(gcc_jit_block_end_with_extended_asm_goto): New entrypoint.
	(gcc_jit_extended_asm_as_object): New entrypoint.
	(gcc_jit_extended_asm_set_volatile_flag): New entrypoint.
	(gcc_jit_extended_asm_set_inline_flag): New entrypoint.
	(gcc_jit_extended_asm_add_output_operand): New entrypoint.
	(gcc_jit_extended_asm_add_input_operand): New entrypoint.
	(gcc_jit_extended_asm_add_clobber): New entrypoint.
	(gcc_jit_context_add_top_level_asm): New entrypoint.
	* libgccjit.map (LIBGCCJIT_ABI_15): New.

gcc/testsuite/ChangeLog:
	PR jit/87291
	* jit.dg/jit.exp: Load target-supports-dg.exp.
	Set dg-do-what-default.
	(jit-dg-test): Set dg-do-what and call dg-get-options, skipping
	the test if it's not supported on the given target.
	* jit.dg/test-asm.c: New test.
	* jit.dg/test-asm.cc: New test.

1 files changed, 103 insertions, 0 deletions

diff --git a/gcc/jit/libgccjit.h b/gcc/jit/libgccjit.h
index 7fbaa9f..c523f93 100644
--- a/gcc/jit/libgccjit.h
+++ b/gcc/jit/libgccjit.h
@@ -68,6 +68,7 @@ typedef struct gcc_jit_result gcc_jit_result;
 	     +- gcc_jit_lvalue
 		 +- gcc_jit_param
 	 +- gcc_jit_case
+	 +- gcc_jit_extended_asm
 */
 typedef struct gcc_jit_object gcc_jit_object;
 
@@ -138,6 +139,12 @@ typedef struct gcc_jit_param gcc_jit_param;
    destination block.  */
 typedef struct gcc_jit_case gcc_jit_case;
 
+/* A gcc_jit_extended_asm represents an assembly language statement,
+   analogous to an extended "asm" statement in GCC's C front-end: a series
+   of low-level instructions inside a function that convert inputs to
+   outputs.  */
+typedef struct gcc_jit_extended_asm gcc_jit_extended_asm;
+
 /* Acquire a JIT-compilation context.  */
 extern gcc_jit_context *
 gcc_jit_context_acquire (void);
@@ -1518,6 +1525,102 @@ gcc_jit_version_minor (void);
 extern int
 gcc_jit_version_patchlevel (void);
 
+/**********************************************************************
+ Asm support.
+ **********************************************************************/
+
+/* Functions for adding inline assembler code, analogous to GCC's
+   "extended asm" syntax.
+
+   See https://gcc.gnu.org/onlinedocs/gcc/Using-Assembly-Language-with-C.html
+
+   These API entrypoints were added in LIBGCCJIT_ABI_15; you can test for their
+   presence using
+     #ifdef LIBGCCJIT_HAVE_ASM_STATEMENTS
+*/
+
+#define LIBGCCJIT_HAVE_ASM_STATEMENTS
+
+/* Create a gcc_jit_extended_asm for an extended asm statement
+   with no control flow (i.e. without the goto qualifier).
+
+   The asm_template parameter  corresponds to the AssemblerTemplate
+   within C's extended asm syntax.  It must be non-NULL.  */
+
+extern gcc_jit_extended_asm *
+gcc_jit_block_add_extended_asm (gcc_jit_block *block,
+				gcc_jit_location *loc,
+				const char *asm_template);
+
+/* Create a gcc_jit_extended_asm for an extended asm statement
+   that may perform jumps, and use it to terminate the given block.
+   This is equivalent to the "goto" qualifier in C's extended asm
+   syntax.  */
+
+extern gcc_jit_extended_asm *
+gcc_jit_block_end_with_extended_asm_goto (gcc_jit_block *block,
+					  gcc_jit_location *loc,
+					  const char *asm_template,
+					  int num_goto_blocks,
+					  gcc_jit_block **goto_blocks,
+					  gcc_jit_block *fallthrough_block);
+
+/* Upcasting from extended asm to object.  */
+
+extern gcc_jit_object *
+gcc_jit_extended_asm_as_object (gcc_jit_extended_asm *ext_asm);
+
+/* Set whether the gcc_jit_extended_asm has side-effects, equivalent to
+   the "volatile" qualifier in C's extended asm syntax.  */
+
+extern void
+gcc_jit_extended_asm_set_volatile_flag (gcc_jit_extended_asm *ext_asm,
+					int flag);
+
+/* Set the equivalent of the "inline" qualifier in C's extended asm
+   syntax.  */
+
+extern void
+gcc_jit_extended_asm_set_inline_flag (gcc_jit_extended_asm *ext_asm,
+				      int flag);
+
+/* Add an output operand to the extended asm statement.
+   "asm_symbolic_name" can be NULL.
+   "constraint" and "dest" must be non-NULL.
+   This function can't be called on an "asm goto" as such instructions
+   can't have outputs  */
+
+extern void
+gcc_jit_extended_asm_add_output_operand (gcc_jit_extended_asm *ext_asm,
+					 const char *asm_symbolic_name,
+					 const char *constraint,
+					 gcc_jit_lvalue *dest);
+
+/* Add an input operand to the extended asm statement.
+   "asm_symbolic_name" can be NULL.
+   "constraint" and "src" must be non-NULL.  */
+
+extern void
+gcc_jit_extended_asm_add_input_operand (gcc_jit_extended_asm *ext_asm,
+					const char *asm_symbolic_name,
+					const char *constraint,
+					gcc_jit_rvalue *src);
+
+/* Add "victim" to the list of registers clobbered by the extended
+   asm statement.  It must be non-NULL.  */
+
+extern void
+gcc_jit_extended_asm_add_clobber (gcc_jit_extended_asm *ext_asm,
+				  const char *victim);
+
+/* Add "asm_stmts", a set of top-level asm statements, analogous to
+   those created by GCC's "basic" asm syntax in C at file scope.  */
+
+extern void
+gcc_jit_context_add_top_level_asm (gcc_jit_context *ctxt,
+				   gcc_jit_location *loc,
+				   const char *asm_stmts);
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */