Hi this patch solves problem with negative frequency that is result of overflow in profile updating code. The testcase shows quite pathological case where profile is misguessed and the mistake is propagated across the CFG by jump threading. I can't of think of much better solution than adding a capping to that code. It should not have bad effect, since frequency will be hot anyway.
Bootstrapped/regtested x86_64-linux, comitted. Honza Index: ChangeLog =================================================================== *** ChangeLog (revision 182685) --- ChangeLog (working copy) *************** *** 1,3 **** --- 1,8 ---- + 2011-12-25 Jan Hubicka <j...@suse.cz> + + PR middle-end/48641 + * tree-ssa-threadupdate.c (redirect_edges): Watch for overflow. + 2011-12-23 Richard Henderson <r...@redhat.com> * tree.def (VEC_EXTRACT_EVEN_EXPR, VEC_EXTRACT_ODD_EXPR): Remove. Index: tree-ssa-threadupdate.c =================================================================== *** tree-ssa-threadupdate.c (revision 182676) --- tree-ssa-threadupdate.c (working copy) *************** redirect_edges (void **slot, void *data) *** 513,519 **** e->src->index, e->dest->index, rd->dup_block->index); rd->dup_block->count += e->count; ! rd->dup_block->frequency += EDGE_FREQUENCY (e); EDGE_SUCC (rd->dup_block, 0)->count += e->count; /* Redirect the incoming edge to the appropriate duplicate block. */ --- 513,523 ---- e->src->index, e->dest->index, rd->dup_block->index); rd->dup_block->count += e->count; ! ! /* Excessive jump threading may make frequencies large enough so ! the computation overflows. */ ! if (rd->dup_block->frequency < BB_FREQ_MAX * 2) ! rd->dup_block->frequency += EDGE_FREQUENCY (e); EDGE_SUCC (rd->dup_block, 0)->count += e->count; /* Redirect the incoming edge to the appropriate duplicate block. */ Index: testsuite/gcc.c-torture/compile/pr48641.c =================================================================== *** testsuite/gcc.c-torture/compile/pr48641.c (revision 0) --- testsuite/gcc.c-torture/compile/pr48641.c (revision 0) *************** *** 0 **** --- 1,249 ---- + /* { dg-options "-O -fno-tree-ccp -fno-tree-copy-prop" } */ + #define CSF __builtin_copysignf + #define CSD __builtin_copysign + #define CSL __builtin_copysignl + #define MODFF __builtin_modff + #define MODFD __builtin_modf + #define MODFL __builtin_modfl + + extern void link_error (void); + + void + foo (void) + { + float iptrf; + double iptr; + long double iptrl; + long long iptrll; + if ((CSF (1.0F, MODFF (0x1p10F + 0.5f, &iptrf)) != CSF (1.0F, 0.5f)) + || (CSF (1.0F, iptrf) != 0x1p10f)) + link_error (); + if (MODFD (0x1p10F + 0.5, &iptr) != 0.5 + || (CSD (1.0, MODFD (0x1p10F + 0.5, &iptr)) != CSD (1.0, 0.5)) + || (CSD (1.0, iptr) != CSD (1.0, 0x1p10))) + link_error (); + if (MODFL (0x1p10F + 0.5l, &iptrl) != 0.5l + || (CSL (1.0L, MODFL (0x1p10F + 0.5l, &iptrl)) != CSL (1.0L, 0.5l)) + || (CSL (1.0L, iptrl) != CSL (1.0L, 0x1p10l))) + link_error (); + if ((CSF (1.0F, (MODFF (0x1p10F + 0x1p-10f, &iptrf))) + != CSF (1.0F, 0x1p-10f)) + || (CSF (1.0F, iptrf) != CSF (1.0F, 0x1p10f))) + link_error (); + if (MODFD (0x1p10F + 0x1p-10, &iptr) != 0x1p-10 + || (CSD (1.0, (MODFD (0x1p10F + 0x1p-10, &iptr))) + != CSD (1.0, 0x1p-10)) || (CSD (1.0, iptr) != CSD (1.0, 0x1p10))) + link_error (); + if (MODFL (0x1p10F + 0x1p-10l, &iptrl) != 0x1p-10l + || (CSL (1.0L, (MODFL (0x1p10F + 0x1p-10l, &iptrl))) + != CSL (1.0L, 0x1p-10l)) + || (CSL (1.0L, iptrl) != CSL (1.0L, 0x1p10l))) + link_error (); + if ((CSF (1.0F, (MODFF (12345678L / 17.0f, &iptrf))) + != CSF (1.0F, (-726216L + 12345678L / 17.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, 726216.0f))) + link_error (); + if (MODFD (12345678L / 17.0, &iptr) != -726216L + 12345678L / 17.0 + || (CSD (1.0, (MODFD (12345678L / 17.0, &iptr))) + != CSD (1.0, (-726216L + 12345678L / 17.0))) + || (CSD (1.0, iptr) != CSD (1.0, 726216.0))) + link_error (); + if ((CSL (1.0L, (MODFL (12345678L / 17.0l, &iptrl))) + != CSL (1.0L, (-726216L + 12345678L / 17.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, 726216.0l))) + link_error (); + if (MODFF (555.555f, &iptrf) != -555 + 555.555f + || (CSF (1.0F, iptrf) != CSF (1.0F, 555.0f))) + link_error (); + if (MODFD (555.555, &iptr) != -555 + 555.555 + || (CSD (1.0, (MODFD (555.555, &iptr))) != CSD (1.0, (-555 + 555.555))) + || (CSD (1.0, iptr) != CSD (1.0, 555.0))) + link_error (); + if (MODFL (555.555l, &iptrl) != -555 + 555.555l + || (CSL (1.0L, (MODFL (555.555l, &iptrl))) + != CSL (1.0L, (-555 + 555.555l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, 555.0l))) + link_error (); + if (MODFF (5000 / 11.0f, &iptrf) != -454 + 5000 / 11.0f + || (CSF (1.0F, (MODFF (5000 / 11.0f, &iptrf))) + != CSF (1.0F, (-454 + 5000 / 11.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, 454.0f))) + link_error (); + if (MODFD (5000 / 11.0, &iptr) != -454 + 5000 / 11.0 + || (CSD (1.0, (MODFD (5000 / 11.0, &iptr))) + != CSD (1.0, (-454 + 5000 / 11.0))) + || (CSD (1.0, iptr) != CSD (1.0, 454.0))) + link_error (); + if ((CSL (1.0L, (MODFL (5000 / 11.0l, &iptrl))) + != CSL (1.0L, (-454 + 5000 / 11.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, 454.0l))) + link_error (); + if ((CSF (1.0F, (MODFF (1000 / 7.0f, &iptrf))) + != CSF (1.0F, (-142 + 1000 / 7.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, 142.0f))) + link_error (); + if ((CSD (1.0, (MODFD (1000 / 7.0, &iptr))) + != CSD (1.0, (-142 + 1000 / 7.0))) + || (CSD (1.0, iptr) != CSD (1.0, 142.0))) + link_error (); + if ((CSL (1.0L, (MODFL (1000 / 7.0l, &iptrl))) + != CSL (1.0L, (-142 + 1000 / 7.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, 142.0l))) + link_error (); + if (MODFF (123 / 7.0f, &iptrf) != -17 + 123 / 7.0f + || (CSF (1.0F, iptrf) != CSF (1.0F, 17.0f))) + link_error (); + if (MODFD (123 / 7.0, &iptr) != -17 + 123 / 7.0 + || (CSD (1.0, iptr) != CSD (1.0, 17.0))) + link_error (); + if ((CSL (1.0L, (MODFL (123 / 7.0l, &iptrl))) + != CSL (1.0L, (-17 + 123 / 7.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, 17.0l))) + link_error (); + if ((CSF (1.0F, (MODFF (117 / 7.0f, &iptrf))) + != CSF (1.0F, (-16 + 117 / 7.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, 16.0f))) + link_error (); + if ((CSD (1.0, (MODFD (117 / 7.0, &iptr))) != CSD (1.0, (-16 + 117 / 7.0))) + || (CSD (1.0, iptr) != CSD (1.0, 16.0))) + link_error (); + if (MODFL (117 / 7.0l, &iptrl) != -16 + 117 / 7.0l + || (CSL (1.0L, iptrl) != CSL (1.0L, 16.0l))) + link_error (); + if (MODFF (5.5f, &iptrf) != 0.5f || (CSF (1.0F, iptrf) != CSF (1.0F, 5.0f))) + link_error (); + if (MODFD (5.5, &iptr) != 0.5 || (CSD (1.0, iptr) != CSD (1.0, 5.0))) + link_error (); + if (MODFL (5.5l, &iptrl) != 0.5l || (CSL (1.0L, iptrl) != CSL (1.0L, 5.0l))) + link_error (); + if ((CSF (1.0F, (MODFF (1.5f, &iptrf))) != CSF (1.0F, 0.5f)) + || (CSF (1.0F, iptrf) != 1.0f)) + link_error (); + if ((CSD (1.0, (MODFD (1.5, &iptr))) != CSD (1.0, 0.5)) + || (CSD (1.0, iptr) != 1.0)) + link_error (); + if (MODFL (1.5l, &iptrl) != iptrl != 1.0l || (CSL (1.0L, iptrl) != 1.0l)) + link_error (); + if (MODFF (4 / 3.0f, &iptrf) != -1 + 4 / 3.0f + || (CSF (1.0F, (MODFF (4 / 3.0f, &iptrf))) + != CSF (1.0F, (-1 + 4 / 3.0f))) || (CSF (1.0F, iptrf) != (1.0F))) + link_error (); + if (MODFD (4 / 3.0, &iptr) != -1 + 4 / 3.0 || (CSD (1.0, iptr) != 1.0)) + link_error (); + if (MODFL (4 / 3.0l, &iptrl) != iptrl != 1.0l + || (CSL (1.0L, iptrl) != 1.0l)) + link_error (); + if ((((MODFF (1.0f, &iptrf)))) || (CSF (1.0F, iptrf) != 1.0f)) + link_error (); + if ((((MODFD (1.0, &iptr))) != 0.0) || (CSD (1.0, iptr) != 1.0)) + link_error (); + if ((((MODFL (1.0l, &iptrl))) != 0.0l) || (CSL (1.0L, iptrl) != 1.0l)) + link_error (); + if (MODFF (0.5f, &iptrf) != 0.5f || (CSF (1.0F, iptrf) != CSF (1.0F, 0.0f))) + link_error (); + if (MODFD (0.5, &iptr) != 0.5 || (CSD (1.0, iptr) != CSD (1.0, 0.0))) + link_error (); + if ((CSL (1.0L, (MODFL (0.5l, &iptrl))) != CSL (1.0L, 0.5l)) + || (CSL (1.0L, iptrl) != CSL (1.0L, 0.0l))) + link_error (); + if (MODFF (4 / 9.0f, &iptrf) != 4 / 9.0f + != (CSF (1.0F, (MODFF (4 / 9.0f, &iptrf))) != CSF (1.0F, (4 / 9.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, 0.0f))) + link_error (); + if (MODFD (4 / 9.0, &iptr) != 4 / 9.0 + || (CSD (1.0, iptr) != CSD (1.0, 0.0))) + link_error (); + if (MODFL (4 / 9.0l, &iptrl) != 4 / 9.0l + || (CSL (1.0L, iptrl) != CSL (1.0L, 0.0l))) + link_error (); + if (MODFF (1 / 3.0f, &iptrf) != 1 / 3.0f + || (CSF (1.0F, iptrf) != CSF (1.0F, 0.0f))) + link_error (); + if (MODFD (1 / 3.0, &iptr) != 1 / 3.0 + || (CSD (1.0, iptr) != CSD (1.0, 0.0))) + link_error (); + if ((CSL (1.0L, (MODFL (1 / 3.0l, &iptrl))) != CSL (1.0L, (1 / 3.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, 0.0l))) + link_error (); + if ((CSF (1.0F, (MODFF (1 / 9.0f, &iptrf))) != CSF (1.0F, (1 / 9.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, 0.0f))) + link_error (); + if (MODFD (1 / 9.0, &iptr) != 1 / 9.0 + || (CSD (1.0, iptr) != CSD (1.0, 0.0))) + link_error (); + if ((CSL (1.0L, (MODFL (1 / 9.0l, &iptrl))) != CSL (1.0L, (1 / 9.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, 0.0l))) + link_error (); + if ((((MODFF (0.0f, &iptrf)))) || (CSF (1.0F, iptrf) != CSF (1.0F, 0.0f))) + link_error (); + if ((((MODFD (0.0, &iptr)))) || (CSD (1.0, iptr) != CSD (1.0, 0.0))) + link_error (); + if ((((MODFL (0.0l, &iptrl))) != 0.0l) + || (CSL (1.0L, iptrl) != CSL (1.0L, 0.0l))) + link_error (); + if ((((MODFF (-0.0f, &iptrf)))) || (CSF (1.0F, iptrf) != CSF (1.0F, -0.0f))) + link_error (); + if ((((MODFD (-0.0, &iptr)))) || (CSD (1.0, iptr) != CSD (1.0, -0.0))) + link_error (); + if ((CSL (1.0L, (MODFL (-0.0l, &iptrl))) != CSL (1.0L, -0.0l)) + || (CSL (1.0L, iptrl) != CSL (1.0L, -0.0l))) + link_error (); + if (MODFF (-1 / 9.0f, &iptrf) != -1 / 9.0f + || (CSF (1.0F, (MODFF (-1 / 9.0f, &iptrf))) != CSF (1.0F, (-1 / 9.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, -0.0f))) + link_error (); + if (MODFD (-1 / 9.0, &iptr) != -1 / 9.0 + || (CSD (1.0, iptr) != CSD (1.0, -0.0))) + link_error (); + if ((CSL (1.0L, (MODFL (-1 / 9.0l, &iptrl))) != CSL (1.0L, (-1 / 9.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, -0.0l))) + link_error (); + if ((CSF (1.0F, (MODFF (-1 / 3.0f, &iptrf))) != CSF (1.0F, (-1 / 3.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, -0.0f))) + link_error (); + if (MODFD (-1 / 3.0, &iptr) != -1 / 3.0 + || (CSD (1.0, iptr) != CSD (1.0, -0.0))) + link_error (); + if ((CSL (1.0L, (MODFL (-1 / 3.0l, &iptrl))) != CSL (1.0L, (-1 / 3.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, -0.0l))) + link_error (); + if (MODFF (-4 / 9.0f, &iptrf) != -4 / 9.0f + || (CSF (1.0F, (MODFF (-4 / 9.0f, &iptrf))) != CSF (1.0F, (-4 / 9.0f))) + || (CSF (1.0F, iptrf) != CSF (1.0F, -0.0f))) + link_error (); + if (MODFD (-4 / 9.0, &iptr) != -4 / 9.0 + || (CSD (1.0, iptr) != CSD (1.0, -0.0))) + link_error (); + if (MODFL (-4 / 9.0l, &iptrl) != -4 / 9.0l + || (CSL (1.0L, (MODFL (-4 / 9.0l, &iptrl))) != CSL (1.0L, (-4 / 9.0l))) + || (CSL (1.0L, iptrl) != CSL (1.0L, -0.0l))) + link_error (); + if (MODFF (-0.5f, &iptrf) != -0.5f + || (CSF (1.0F, iptrf) != CSF (1.0F, -0.0f))) + link_error (); + if (MODFD (-0.5, &iptr) != -0.5 + != (CSD (1.0, (MODFD (-0.5, &iptr))) != CSD (1.0, -0.5)) + || (CSD (1.0, iptr) != CSD (1.0, -0.0))) + (MODFL (-0.5l, (long double *) &iptrll)); + if ((((MODFF (-1.0f, &iptrf)))) || (CSF (1.0F, iptrf) != -1.0f)) + link_error (); + if ((((MODFD (-1.0, &iptr))) != -0.0) || (CSD (1.0, iptr) != -1.0)) + link_error (); + if ((((MODFL (-1.0l, &iptrl)))) || (CSL (1.0L, iptrl) != -1.0l)) + link_error (); + if ((CSF (1.0F, (MODFF (-4 / 3.0f, &iptrf))) != CSF (1.0F, (1 - 4 / 3.0f))) + || (CSF (1.0F, iptrf) != -1.0f)) + link_error (); + if (MODFD (-4 / 3.0, &iptr) != 1 - 4 / 3.0 || (CSD (1.0, iptr) != -1.0)) + link_error (); + if (MODFL (-4 / 3.0l, &iptrl) != 1 - 4 / 3.0l + || (CSL (1.0L, (MODFL (-4 / 3.0l, &iptrl))) + != CSL (1.0L, (1 - 4 / 3.0l))) || (CSL (1.0L, iptrl) != -1.0l)) + link_error (); + if ((CSF (1.0F, (MODFF (-1.5f, &iptrf))) != CSF (1.0F, -0.5f)) + || (CSF (1.0F, iptrf) != -1.0f)) + link_error (); + if ((CSD (1.0, (MODFD (-1.5, &iptr))) != CSD (1.0, -0.5)) + || (CSD (1.0, iptr) != -1.0)) + link_error (); + } Index: testsuite/ChangeLog =================================================================== *** testsuite/ChangeLog (revision 182676) --- testsuite/ChangeLog (working copy) *************** *** 1,3 **** --- 1,8 ---- + 2011-12-25 Jan Hubicka <j...@suse.cz> + + PR middle-end/48641 + * gcc.dg/compile/pr48641.c: New file. + 2011-12-23 Jason Merrill <ja...@redhat.com> PR c++/51507