re PR rtl-optimization/59137 (Miscompilation at -O1 on mips/mipsel)

gcc/
	PR rtl-optimization/59137
	* reorg.c (steal_delay_list_from_target): Call update_block for
	elided insns.
	(steal_delay_list_from_fallthrough, relax_delay_slots): Likewise.

gcc/testsuite/
	PR rtl-optimization/59137
	* gcc.target/mips/pr59137.c: New test.

From-SVN: r206445

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8d61a49724fb3e14ad854fdfea177d9917ea8f76..2826bca98bd2efc52d5c85b613a77b2082593bc0 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2014-01-08  Richard Sandiford  <rdsandiford@googlemail.com>
+
+       PR rtl-optimization/59137
+       * reorg.c (steal_delay_list_from_target): Call update_block for
+       elided insns.
+       (steal_delay_list_from_fallthrough, relax_delay_slots): Likewise.
+
 2014-01-08  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
 
        * config/rs6000/rs6000-c.c (altivec_overloaded_builtins): Remove

diff --git a/gcc/reorg.c b/gcc/reorg.c
index 740da4a83c6ce314a8d0a171bb4770c717ed62d0..de332323ae1c155883ebaf19f8cd064390058380 100644 (file)
--- a/gcc/reorg.c
+++ b/gcc/reorg.c
@@ -1093,6 +1093,7 @@ steal_delay_list_from_target (rtx insn, rtx condition, rtx seq,
   int used_annul = 0;
   int i;
   struct resources cc_set;
+  bool *redundant;
 
   /* We can't do anything if there are more delay slots in SEQ than we
      can handle, or if we don't know that it will be a taken branch.
@@ -1133,6 +1134,7 @@ steal_delay_list_from_target (rtx insn, rtx condition, rtx seq,
     return delay_list;
 #endif
 
+  redundant = XALLOCAVEC (bool, XVECLEN (seq, 0));
   for (i = 1; i < XVECLEN (seq, 0); i++)
     {
       rtx trial = XVECEXP (seq, 0, i);
@@ -1154,7 +1156,8 @@ steal_delay_list_from_target (rtx insn, rtx condition, rtx seq,
 
       /* If this insn was already done (usually in a previous delay slot),
         pretend we put it in our delay slot.  */
-      if (redundant_insn (trial, insn, new_delay_list))
+      redundant[i] = redundant_insn (trial, insn, new_delay_list);
+      if (redundant[i])
        continue;
 
       /* We will end up re-vectoring this branch, so compute flags
@@ -1187,6 +1190,12 @@ steal_delay_list_from_target (rtx insn, rtx condition, rtx seq,
        return delay_list;
     }
 
+  /* Record the effect of the instructions that were redundant and which
+     we therefore decided not to copy.  */
+  for (i = 1; i < XVECLEN (seq, 0); i++)
+    if (redundant[i])
+      update_block (XVECEXP (seq, 0, i), insn);
+
   /* Show the place to which we will be branching.  */
   *pnew_thread = first_active_target_insn (JUMP_LABEL (XVECEXP (seq, 0, 0)));
 
@@ -1250,6 +1259,7 @@ steal_delay_list_from_fallthrough (rtx insn, rtx condition, rtx seq,
       /* If this insn was already done, we don't need it.  */
       if (redundant_insn (trial, insn, delay_list))
        {
+         update_block (trial, insn);
          delete_from_delay_slot (trial);
          continue;
        }
@@ -3236,6 +3246,7 @@ relax_delay_slots (rtx first)
         to reprocess this insn.  */
       if (redundant_insn (XVECEXP (pat, 0, 1), delay_insn, 0))
        {
+         update_block (XVECEXP (pat, 0, 1), insn);
          delete_from_delay_slot (XVECEXP (pat, 0, 1));
          next = prev_active_insn (next);
          continue;
@@ -3355,6 +3366,7 @@ relax_delay_slots (rtx first)
              && redirect_with_delay_slots_safe_p (delay_insn, target_label,
                                                   insn))
            {
+             update_block (XVECEXP (PATTERN (trial), 0, 1), insn);
              reorg_redirect_jump (delay_insn, target_label);
              next = insn;
              continue;

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 13334a4fb1bc0a5404672fd552bdf09b47145278..3319675a210526f23f0bf7bf5cee57fdbcd6bb4d 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2014-01-08  Richard Sandiford  <rdsandiford@googlemail.com>
+
+       PR rtl-optimization/59137
+       * gcc.target/mips/pr59137.c: New test.
+
 2014-01-08  Uros Bizjak  <ubizjak@gmail.com>
 
        * gcc.target/i386/asm-1.c (dg-options): Remove -m32.

diff --git a/gcc/testsuite/gcc.target/mips/pr59137.c b/gcc/testsuite/gcc.target/mips/pr59137.c
new file mode 100644 (file)
index 0000000..8986506
--- /dev/null
+++ b/gcc/testsuite/gcc.target/mips/pr59137.c
@@ -0,0 +1,34 @@
+/* { dg-do run } */
+/* { dg-options "-mno-plt" } */
+
+extern void abort (void);
+
+struct lispstruct
+{
+  int e;
+  int t;
+};
+
+struct lispstruct Cnil_body;
+struct lispstruct Ct_body;
+int nvalues;
+
+struct lispstruct * __attribute__ ((noinline))
+fLlistp (struct lispstruct *x0)
+{
+  if (x0 == &Cnil_body
+      || (((unsigned long) x0 >= 0x80000000) ? 0
+         : (!x0->e ? (x0 != &Cnil_body) : x0->t)))
+    x0 = &Ct_body;
+  else
+    x0 = &Cnil_body;
+  nvalues = 1;
+  return x0;
+}
+
+int main ()
+{
+  if (fLlistp ((struct lispstruct *) 0xa0000001) != &Cnil_body)
+    abort ();
+  return 0;
+}