compare-elim: Fix an RTL checking failure

find_flags_uses_in_insn used SET_SRC without first checking
for a SET.  This showed up as an RTL checking failure in
g++.dg/torture/pr90994.C on aarch64.

gcc/
	* compare-elim.cc (find_flags_uses_in_insn): Guard use of SET_SRC.

diff --git a/gcc/compare-elim.cc b/gcc/compare-elim.cc
index 5cbd2c027b1dd55948479263eedb6b97f74d4de3..c59dc0cf5a53d93c8e26e03990ef923beb50c2b0 100644 (file)
--- a/gcc/compare-elim.cc
+++ b/gcc/compare-elim.cc
@@ -254,7 +254,8 @@ find_flags_uses_in_insn (struct comparison *cmp, rtx_insn *insn)
        x = PATTERN (insn);
        if (GET_CODE (x) == PARALLEL)
          x = XVECEXP (x, 0, 0);
-       x = SET_SRC (x);
+       if (GET_CODE (x) == SET)
+         x = SET_SRC (x);
        if (GET_CODE (x) == IF_THEN_ELSE)
          x = XEXP (x, 0);
        if (COMPARISON_P (x)