[Bug target/80706] [7/8 Regression] peephole2 uses uninitialized stack variables on i686

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80706

--- Comment #7 from Uroš Bizjak <ubizjak at gmail dot com> ---
(In reply to Uroš Bizjak from comment #5)

--cut here--
diff --git a/gcc/config/i386/sync.md b/gcc/config/i386/sync.md
index 20d46fe..895a1ea 100644
--- a/gcc/config/i386/sync.md
+++ b/gcc/config/i386/sync.md
@@ -222,7 +222,8 @@
   "!TARGET_64BIT
    && peep2_reg_dead_p (2, operands[0])
    && rtx_equal_p (operands[4], adjust_address_nv (operands[2], DFmode, 0))"
-  [(set (match_dup 3) (match_dup 5))]
+  [(set (match_dup 3) (match_dup 5))
+   (set (match_dup 4) (match_dup 3))]
   "operands[5] = gen_lowpart (DFmode, operands[1]);")

 (define_peephole2
@@ -235,7 +236,8 @@
   "!TARGET_64BIT
    && peep2_reg_dead_p (2, operands[0])
    && rtx_equal_p (operands[4], adjust_address_nv (operands[2], DFmode, 0))"
-  [(set (match_dup 3) (match_dup 5))]
+  [(set (match_dup 3) (match_dup 5))
+   (set (match_dup 4) (match_dup 3))]
   "operands[5] = gen_lowpart (DFmode, operands[1]);")

 (define_expand "atomic_store<mode>"
@@ -338,7 +340,8 @@
   "!TARGET_64BIT
    && peep2_reg_dead_p (3, operands[2])
    && rtx_equal_p (operands[0], adjust_address_nv (operands[3], DFmode, 0))"
-  [(set (match_dup 5) (match_dup 1))]
+  [(set (match_dup 5) (match_dup 1))
+   (set (match_dup 0) (match_dup 1))]
   "operands[5] = gen_lowpart (DFmode, operands[4]);")

 (define_peephole2
@@ -351,7 +354,8 @@
   "!TARGET_64BIT
    && peep2_reg_dead_p (3, operands[2])
    && rtx_equal_p (operands[0], adjust_address_nv (operands[3], DFmode, 0))"
-  [(set (match_dup 5) (match_dup 1))]
+  [(set (match_dup 5) (match_dup 1))
+   (set (match_dup 0) (match_dup 1))]
   "operands[5] = gen_lowpart (DFmode, operands[4]);")

 ;; ??? You'd think that we'd be able to perform this via FLOAT + FIX_TRUNC
--cut here--

> Jakub, does the above patch fix the failure?

Bah, cut-n-pasto... the above should be correct patch.