jit: add support for inline asm [PR87291]

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.