On Tue, Dec 27, 2011 at 11:44 AM, Jan Hubicka <hubi...@ucw.cz> wrote:
> 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);
I think this really asks for some (inline) helpers that do frequency adjustment
(and properly saturate, which is missing in the above case).
Richard.
> 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
