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[PATCH] Fix PR61801, sched2 vs. debug-insns

This fixes a miscompile of glibc trunk on i?86 which happens because
the sched-deps treats a debug-insn with volatile ASM_OPERANDS
as a barrier.

Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.

Ok for trunk and branches?


2014-07-16  Richard Biener  <>

	PR rtl-optimization/61801
	* sched-deps.c (sched_analyze_2): For ASM_OPERANDS and
	ASM_INPUT don't set reg_pending_barrier if it appears in a

Index: gcc/sched-deps.c
--- gcc/sched-deps.c	(revision 212580)
+++ gcc/sched-deps.c	(working copy)
@@ -2750,7 +2750,8 @@ sched_analyze_2 (struct deps_desc *deps,
 	   Consider for instance a volatile asm that changes the fpu rounding
 	   mode.  An insn should not be moved across this even if it only uses
 	   pseudo-regs because it might give an incorrectly rounded result.  */
-	if (code != ASM_OPERANDS || MEM_VOLATILE_P (x))
+	if ((code != ASM_OPERANDS || MEM_VOLATILE_P (x))
+	    && !DEBUG_INSN_P (insn))
 	  reg_pending_barrier = TRUE_BARRIER;
 	/* For all ASM_OPERANDS, we must traverse the vector of input operands.

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