Backport PR69941 patch from mainline.

	PR rtl-optimization/69941
	* postreload.c (reload_combine_recognize_pattern): Ensure all uses of
	the reg share its mode.

	PR rtl-optimization/69941
	* gcc.dg/torture/pr69941.c: New test.

From-SVN: r234209

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index c626a6f9d526c759491a05515827a2bce3b27a43..1225cac52f7aeaf7d9c5f5c1ceb89d8a2308d6a3 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2016-03-15  Bernd Schmidt  <bschmidt@redhat.com>
+
+       Backport from mainline
+       2016-03-04  Bernd Schmidt  <bschmidt@redhat.com>
+
+       PR rtl-optimization/69941
+       * postreload.c (reload_combine_recognize_pattern): Ensure all uses of
+       the reg share its mode.
+
 2016-03-14  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>
 
        Backport from mainline:

diff --git a/gcc/postreload.c b/gcc/postreload.c
index 9bfffe5f4df4290da668a73a9700cc56f09ea239..1e852cdde043c864170d742aa2bee87d52ca527e 100644 (file)
--- a/gcc/postreload.c
+++ b/gcc/postreload.c
@@ -1094,7 +1094,6 @@ static bool
 reload_combine_recognize_pattern (rtx insn)
 {
   rtx set, reg, src;
-  unsigned int regno;
 
   set = single_set (insn);
   if (set == NULL_RTX)
@@ -1106,7 +1105,20 @@ reload_combine_recognize_pattern (rtx insn)
       || hard_regno_nregs[REGNO (reg)][GET_MODE (reg)] != 1)
     return false;
 
-  regno = REGNO (reg);
+  unsigned int regno = REGNO (reg);
+  machine_mode mode = GET_MODE (reg);
+
+  if (reg_state[regno].use_index < 0
+      || reg_state[regno].use_index >= RELOAD_COMBINE_MAX_USES)
+    return false;
+
+  for (int i = reg_state[regno].use_index;
+       i < RELOAD_COMBINE_MAX_USES; i++)
+    {
+      struct reg_use *use = reg_state[regno].reg_use + i;
+      if (GET_MODE (*use->usep) != mode)
+       return false;
+    }
 
   /* Look for (set (REGX) (CONST_INT))
      (set (REGX) (PLUS (REGX) (REGY)))
@@ -1128,8 +1140,6 @@ reload_combine_recognize_pattern (rtx insn)
       && REG_P (XEXP (src, 1))
       && rtx_equal_p (XEXP (src, 0), reg)
       && !rtx_equal_p (XEXP (src, 1), reg)
-      && reg_state[regno].use_index >= 0
-      && reg_state[regno].use_index < RELOAD_COMBINE_MAX_USES
       && last_label_ruid < reg_state[regno].use_ruid)
     {
       rtx base = XEXP (src, 1);

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 60cb3d7075ef560a3630f94fd66d94e0ec5bae2f..d75573b994a840e038fd76088e69cdf5235f326d 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2016-03-15  Bernd Schmidt  <bschmidt@redhat.com>
+
+       Backport from mainline
+       2016-03-04  Bernd Schmidt  <bschmidt@redhat.com>
+
+       PR rtl-optimization/69941
+       * gcc.dg/torture/pr69941.c: New test.
+
 2016-03-14  Dominique d'Humieres  <dominiq@lps.ens.fr>
 
        PR fortran/45076

diff --git a/gcc/testsuite/gcc.dg/torture/pr69941.c b/gcc/testsuite/gcc.dg/torture/pr69941.c
new file mode 100644 (file)
index 0000000..f15d41a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr69941.c
@@ -0,0 +1,30 @@
+/* { dg-do run } */
+ 
+int a = 0;
+int b = 0;
+int c = 0;
+int e = 0;
+int f = 0;
+int *g = &e;
+ 
+int fn1() { return b ? a : b; }
+ 
+int main() {
+  int h = fn1() <= 0x8000000000000000ULL; // h = 1;
+ 
+  int k = f; // k = 0;
+ 
+  long i = h ? k : k / h; // i = 0;
+ 
+  long l = (unsigned short)(i - 0x1800); // l = 0xe800
+ 
+  i = l ? l : c; // i = 0xe800;
+ 
+  *g = i; // *g = 0xe800; e = 0xe800;
+ 
+  unsigned char result = e >> 9; // result = 0x74;
+
+  if ((int)result != 0x74)
+    __builtin_abort ();
+  return 0;
+}