On 1/29/07, Grigory Zagorodnev <[EMAIL PROTECTED]> wrote:
Grigory Zagorodnev wrote:
> GCC 4.3 compiler revision 121206 goes into infinitive loop while
> compiling cpu2k6/perlbench source file regcomp.c at -O2 optimization
> level on x86_64-redhat-linux.
This regression is caused by "Rewrite of portions of points-to solver"
patch http://gcc.gnu.org/ml/gcc-patches/2007-01/msg01541.html
revision 120931 http://gcc.gnu.org/viewcvs?view=rev&revision=120931
Patch attached and committed after bootstrap and regtest on i686-darwin.
2007-01-29 Daniel Berlin <[EMAIL PROTECTED]>
* tree-ssa-structalias.c (do_complex_constraint): Mark correct
variable as changed.
- Grigory
Index: testsuite/gcc.c-torture/compile/20070129.c
===================================================================
--- testsuite/gcc.c-torture/compile/20070129.c (revision 0)
+++ testsuite/gcc.c-torture/compile/20070129.c (revision 0)
@@ -0,0 +1,94 @@
+/* This testcase would cause a hang in PTA solving due to a complex copy
+ constraint and marking the wrong variable as changed. */
+
+typedef struct RExC_state_t
+{
+ char *end;
+ char *parse;
+} RExC_state_t;
+
+struct regnode_string
+{
+ unsigned char str_len;
+ char string[1];
+};
+
+static void *regatom (RExC_state_t * pRExC_state, int *flagp);
+
+static void *
+regpiece (RExC_state_t * pRExC_state, int *flagp)
+{
+ return regatom (0, 0);
+}
+
+static void *
+regbranch (RExC_state_t * pRExC_state, int *flagp, int first)
+{
+ return regpiece (0, 0);
+}
+
+static void *
+reg (RExC_state_t * pRExC_state, int paren, int *flagp)
+{
+ return regbranch (0, 0, 1);
+}
+
+void *
+Perl_pregcomp (char *exp, char *xend, void *pm)
+{
+ return reg (0, 0, 0);
+}
+
+static void *
+regatom (RExC_state_t * pRExC_state, int *flagp)
+{
+ register void *ret = 0;
+ int flags;
+
+tryagain:
+ switch (*(pRExC_state->parse))
+ {
+ case '(':
+ ret = reg (pRExC_state, 1, &flags);
+ if (flags & 0x8)
+ {
+ goto tryagain;
+ }
+ break;
+ default:
+ {
+ register unsigned long len;
+ register unsigned ender;
+ register char *p;
+ char *oldp, *s;
+ unsigned long numlen;
+ unsigned long foldlen;
+ unsigned char tmpbuf[6 + 1], *foldbuf;
+
+ defchar:
+ s = (((struct regnode_string *) ret)->string);
+ for (len = 0, p = (pRExC_state->parse) - 1;
+ len < 127 && p < (pRExC_state->end); len++)
+ {
+ if (((*p) == '*' || (*p) == '+' || (*p) == '?'
+ || ((*p) == '{' && regcurly (p))))
+ {
+ unsigned long unilen;
+ for (foldbuf = tmpbuf; foldlen; foldlen -= numlen)
+ {
+ reguni (pRExC_state, ender, s, &unilen);
+ s += unilen;
+ }
+ break;
+ }
+ unsigned long unilen;
+
+ reguni (pRExC_state, ender, s, &unilen);
+ s += unilen;
+ }
+
+ };
+ break;
+ }
+ return (ret);
+}
Index: tree-ssa-structalias.c
===================================================================
--- tree-ssa-structalias.c (revision 121279)
+++ tree-ssa-structalias.c (working copy)
@@ -1538,9 +1538,9 @@ do_complex_constraint (constraint_graph_
if (flag)
{
get_varinfo (t)->solution = tmp;
- if (!TEST_BIT (changed, c->lhs.var))
+ if (!TEST_BIT (changed, t))
{
- SET_BIT (changed, c->lhs.var);
+ SET_BIT (changed, t);
changed_count++;
}
}
@@ -2065,6 +2065,7 @@ solve_graph (constraint_graph_t graph)
bitmap solution;
VEC(constraint_t,heap) *complex = graph->complex[i];
bool solution_empty;
+
RESET_BIT (changed, i);
changed_count--;
