The following patch fixes
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57459
The bug occurs in case of rare combination when insn uses inherited and
original value, the pseudo is input and output and the pseudo value (as
insn result) is unused.
The patch was successfully bootstrapped and tested on x86/x86-64.
Committed as rev. 199762.
2013-06-06 Vladimir Makarov <vmaka...@redhat.com>
PR rtl-optimization/57459
* lra-constraints.c (update_ebb_live_info): Fix typo for operand
type when setting live regs.
2013-06-06 Vladimir Makarov <vmaka...@redhat.com>
PR rtl-optimization/57459
* gcc.target/i386/pr57459.c: New test.
Index: lra-constraints.c
===================================================================
--- lra-constraints.c (revision 199753)
+++ lra-constraints.c (working copy)
@@ -4545,7 +4545,7 @@ update_ebb_live_info (rtx head, rtx tail
bitmap_clear_bit (&live_regs, reg->regno);
/* Mark each used value as live. */
for (reg = curr_id->regs; reg != NULL; reg = reg->next)
- if (reg->type == OP_IN
+ if (reg->type != OP_OUT
&& bitmap_bit_p (&check_only_regs, reg->regno))
bitmap_set_bit (&live_regs, reg->regno);
/* It is quite important to remove dead move insns because it
Index: testsuite/gcc.target/i386/pr57459.c
===================================================================
--- testsuite/gcc.target/i386/pr57459.c (revision 0)
+++ testsuite/gcc.target/i386/pr57459.c (working copy)
@@ -0,0 +1,60 @@
+/* PR rtl-optimization/57459 */
+/* { dg-do run } */
+/* { dg-options "-fno-inline -O2 -minline-all-stringops -fno-omit-frame-pointer" } */
+
+int total1[10], total2[10], total3[10], total4[10], total5[10], a[20];
+int len;
+
+void stackclean() {
+ void *ptr = __builtin_alloca(20000);
+ __builtin_memset(ptr, 0, 20000);
+}
+
+void foo(const char *s) {
+ int r1 = a[1];
+ int r2 = a[2];
+ int r3 = a[3];
+ int r4 = a[4];
+ int r5 = a[5];
+
+ len = __builtin_strlen(s);
+
+ if (s != 0)
+ return;
+
+ while (r1) {
+ total1[r1] = r1;
+ r1--;
+ }
+
+ while (r2) {
+ total2[r2] = r2;
+ r2--;
+ }
+
+ while (r3) {
+ total3[r3] = r3;
+ r3--;
+ }
+
+ while (r4) {
+ total4[r4] = r4;
+ r4--;
+ }
+
+ while (r5) {
+ total5[r5] = r5;
+ r5--;
+ }
+}
+
+extern void abort (void);
+
+int main() {
+ stackclean();
+ foo("abcdefgh");
+ if (len != 8)
+ abort ();
+ return 0;
+}
+
