re PR c/59708 (clang-compatible checked arithmetic builtins)

	PR c/59708
	* builtin-attrs.def (ATTR_NOTHROW_TYPEGENERIC_LEAF): New attribute.
	* builtins.c (fold_builtin_arith_overflow): New function.
	(fold_builtin_3): Use it.
	* builtins.def (BUILT_IN_ADD_OVERFLOW, BUILT_IN_SUB_OVERFLOW,
	BUILT_IN_MUL_OVERFLOW, BUILT_IN_SADD_OVERFLOW, BUILT_IN_SADDL_OVERFLOW,
	BUILT_IN_SADDLL_OVERFLOW, BUILT_IN_SSUB_OVERFLOW,
	BUILT_IN_SSUBL_OVERFLOW, BUILT_IN_SSUBLL_OVERFLOW,
	BUILT_IN_SMUL_OVERFLOW, BUILT_IN_SMULL_OVERFLOW,
	BUILT_IN_SMULLL_OVERFLOW, BUILT_IN_UADDL_OVERFLOW,
	BUILT_IN_UADDLL_OVERFLOW, BUILT_IN_USUB_OVERFLOW,
	BUILT_IN_USUBL_OVERFLOW, BUILT_IN_USUBLL_OVERFLOW,
	BUILT_IN_UMUL_OVERFLOW, BUILT_IN_UMULL_OVERFLOW,
	BUILT_IN_UMULLL_OVERFLOW): New built-in functions.
	* builtin-types.def (BT_PTR_UINT, BT_PTR_ULONG, BT_PTR_LONGLONG,
	BT_FN_BOOL_INT_INT_INTPTR, BT_FN_BOOL_LONG_LONG_LONGPTR,
	BT_FN_BOOL_LONGLONG_LONGLONG_LONGLONGPTR, BT_FN_BOOL_UINT_UINT_UINTPTR,
	BT_FN_BOOL_ULONG_ULONG_ULONGPTR,
	BT_FN_BOOL_ULONGLONG_ULONGLONG_ULONGLONGPTR, BT_FN_BOOL_VAR): New.
	* expr.c (write_complex_part): Remove prototype, no longer static.
	* expr.h (write_complex_part): New prototype.
	* function.c (aggregate_value_p): For internal functions return 0.
	* gimple-fold.c (arith_overflowed_p): New functions.
	(gimple_fold_call): Fold {ADD,SUB,MUL}_OVERFLOW internal calls.
	* gimple-fold.h (arith_overflowed_p): New prototype.
	* tree-ssa-dce.c: Include tree-ssa-propagate.h and gimple-fold.h.
	(find_non_realpart_uses, maybe_optimize_arith_overflow): New
	functions.
	(eliminate_unnecessary_stmts): Transform {ADD,SUB,MUL}_OVERFLOW
	into COMPLEX_CST/COMPLEX_EXPR if IMAGPART_EXPR of the result is
	never used.
	* gimplify.c (gimplify_call_expr): Handle gimplification of
	internal calls with lhs.
	* internal-fn.c (get_range_pos_neg, get_min_precision,
	expand_arith_overflow_result_store): New functions.
	(ubsan_expand_si_overflow_addsub_check): Renamed to ...
	(expand_addsub_overflow): ... this.  Add LOC, LHS, ARG0, ARG1,
	UNSR_P, UNS0_P, UNS1_P, IS_UBSAN arguments, remove STMT argument.
	Handle ADD_OVERFLOW and SUB_OVERFLOW expansion.
	(ubsan_expand_si_overflow_neg_check): Renamed to ...
	(expand_neg_overflow): ... this.  Add LOC, LHS, ARG1, IS_UBSAN
	arguments, remove STMT argument.  Handle SUB_OVERFLOW with
	0 as first argument expansion.
	(ubsan_expand_si_overflow_mul_check): Renamed to ...
	(expand_mul_overflow): ... this.  Add LOC, LHS, ARG0, ARG1,
	UNSR_P, UNS0_P, UNS1_P, IS_UBSAN arguments, remove STMT argument.
	Handle MUL_OVERFLOW expansion.
	(expand_UBSAN_CHECK_ADD): Use expand_addsub_overflow, prepare
	arguments for it.
	(expand_UBSAN_CHECK_SUB): Use expand_addsub_overflow or
	expand_neg_overflow, prepare arguments for it.
	(expand_UBSAN_CHECK_MUL): Use expand_mul_overflow, prepare arguments
	for it.
	(expand_arith_overflow, expand_ADD_OVERFLOW, expand_SUB_OVERFLOW,
	expand_MUL_OVERFLOW): New functions.
	* internal-fn.def (ADD_OVERFLOW, SUB_OVERFLOW, MUL_OVERFLOW): New
	internal functions.
	* tree-vrp.c (check_for_binary_op_overflow): New function.
	(extract_range_basic): Handle {REAL,IMAG}PART_EXPR if the operand
	is SSA_NAME set by {ADD,SUB,MUL}_OVERFLOW internal functions.
	(simplify_internal_call_using_ranges): Handle {ADD,SUB,MUL}_OVERFLOW
	internal functions.
	* optabs.def (umulv4_optab): New optab.
	* config/i386/i386.md (umulv<mode>4, <u>mulvqi4): New define_expands.
	(*umulv<mode>4, *<u>mulvqi4): New define_insns.
	* doc/extend.texi (Integer Overflow Builtins): Document
	__builtin_*_overflow.
c-family/
	* c-common.c (check_builtin_function_arguments): Handle
	BUILT_IN_{ADD,SUB,MUL}_OVERFLOW.
testsuite/
	* c-c++-common/builtin-arith-overflow-1.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-10.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-11.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-12.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-12.h: New file.
	* c-c++-common/torture/builtin-arith-overflow-13.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-14.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-15.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-16.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-17.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-18.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-1.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-1.h: New file.
	* c-c++-common/torture/builtin-arith-overflow-2.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-3.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-4.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-5.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-6.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-7.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-8.c: New test.
	* c-c++-common/torture/builtin-arith-overflow-9.c: New test.
	* c-c++-common/torture/builtin-arith-overflow.h: New file.
	* gcc.dg/builtin-arith-overflow-1.c: New test.
	* gcc.dg/builtin-arith-overflow-2.c: New test.

From-SVN: r217415