2009-10-06  Ian Lance Taylor  <iant@google.com>

	* varasm.c (saw_no_split_stack): New static variable.
	(assemble_start_function): Check for no_split_stack attribute and
	set saw_no_split_stack if we find it.
	(file_end_indicate_split_stack): New function.
	* output.h (file_end_indicate_split_stack): Declare.
	* config/i386/i386.c (ix86_file_end): Call
	file_end_indicate_split_stack.
	(ix86_expand_split_stack_prologue): Use small test if <
	SPLIT_STACK_AVAILABLE, not <=.
	* config/i386/i386.md (split_stack_check_small): Use GEU.
	(split_stack_check_large): Likewise.

2009-09-30  Ian Lance Taylor  <iant@google.com>

	* config/i386/i386.c (ix86_expand_split_stack_prologue): Never
	save %ecx around the call to __morestack.

2009-09-29  Ian Lance Taylor  <iant@google.com>

	* gcc.c (STACK_SPLIT_SPEC): Define.
	(LINK_COMMAND_SPEC): Use STACK_SPLIT_SPEC.
	* config/i386/i386.c (ix86_supports_split_stack): Remove test of
	flag_stack_protect.
	(ix86_expand_split_stack_prologue): Set call insn function usage
	to include register parameters.  Emit return instruction after
	call to __morestack.
	* config/i386/i386.md (split_stack_check_small): Use unsigned
	comparison.
	(split_stack_check_large): Likewise.
	(split_stack_return): New insn.
	* config/i386/linux.h (TARGET_THREAD_SPLIT_STACK_OFFSET): Change
	value.
	* config/i386/linux64.h (TARGET_THREAD_SPLIT_STACK_OFFSET):
	Likewise.

2009-09-25  Ian Lance Taylor  <iant@google.com>

	* testsuite/gcc.dg/split-1.c: New test.
	* testsuite/gcc.dg/split-2.c: New test.
	* testsuite/lib/target-supports.exp
	(check_effective_target_split_stack): New function.

	* config/i386/i386.c (ix86_supports_split_stack): New static
	function.
	(split_stack_fn): New static variable.
	(ix86_expand_split_stack_prologue): New function.
	(ix86_expand_call): Return the new call insn.
	(TARGET_SUPPORTS_SPLIT_STACK): Define.
	* config/i386/i386.md (UNSPEC_STACK_CHECK): Define constant.
	(split_stack_prologue): New expander.
	(split_stack_check_small): New expander.
	(split_stack_compare_small_32): New insn.
	(split_stack_compare_small_64): New insn.
	(split_stack_check_large): New expander.
	(split_stack_compare_large_32): New insn.
	(split_stack_compare_large_64): New insn.
	* config/i386/linux.h (TARGET_THREAD_SPLIT_STACK_OFFSET): Define.
	* config/i386/linux64.h (TARGET_THREAD_SPLIT_STACK_OFFSET):
	Define.
	* config/i386/i386-protos.h (ix86_expand_split_stack_prologue):
	Declare.
	(ix86_expand_call): Change return type in declaration.

	* common.opt (fsplit-stack): New option.
	* opts.c (decode_options): Set flag_split_stack.
	* target.h (struct gcc_target): Add supports_split_stack field.
	* target-def.h (TARGET_SUPPORTS_SPLIT_STACK): Define.
	(TARGET_INITIALIZER): Add TARGET_SUPPORTS_SPLIT_STACK.
	* function.c (thread_prologue_and_epilogue_insns): Support
	flag_split_stack.
	* cfgbuild.c (make_label_edge): Add insn parameter.  Change all
	callers.
	* c-common.c (c_common_attribute_table): Add "no_split_stack".
	(handle_no_split_stack_attribute): New static function.


Copyright (C) 2009 Free Software Foundation, Inc.

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