From: Richard Biener Date: Wed, 18 Feb 2015 09:48:57 +0000 (+0000) Subject: re PR tree-optimization/62217 (DOM confuses complete unrolling which in turn causes... X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=6f423f4c894fe9dada8ad862b237001c99aa6150;p=gcc.git re PR tree-optimization/62217 (DOM confuses complete unrolling which in turn causes VRP to warn) 2015-02-18 Richard Biener PR tree-optimization/62217 * tree-ssa-dom.c (cprop_operand): Avoid propagating copies into BIVs. * gcc.dg/tree-ssa/cunroll-11.c: New testcase. From-SVN: r220785 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 2b06a25c6e6..6ede45769ad 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2015-02-18 Richard Biener + + PR tree-optimization/62217 + * tree-ssa-dom.c (cprop_operand): Avoid propagating copies + into BIVs. + 2015-02-18 Marek Polacek PR sanitizer/65081 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index b277f57054e..0a1a328c7f0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2015-02-18 Richard Biener + + PR tree-optimization/62217 + * gcc.dg/tree-ssa/cunroll-11.c: New testcase. + 2015-02-18 Marek Polacek PR sanitizer/65081 diff --git a/gcc/testsuite/gcc.dg/tree-ssa/cunroll-11.c b/gcc/testsuite/gcc.dg/tree-ssa/cunroll-11.c new file mode 100644 index 00000000000..a26cb22d35d --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/cunroll-11.c @@ -0,0 +1,18 @@ +/* { dg-do compile } */ +/* { dg-options "-O3 -Warray-bounds -fdump-tree-cunroll-details" } */ + +typedef struct { unsigned data; } s1; +s1 g_x[4]; + +extern void foo (s1 *x1, s1 *x2, int a, int b) +{ + int i; + for(i = 0; i < a; i++) + if(i == b) + g_x[i] = *x1; + else + g_x[i] = *x2; +} + +/* { dg-final { scan-tree-dump "Loop 1 iterates at most 3 times" "cunroll" } } */ +/* { dg-final { cleanup-tree-dump "cunroll" } } */ diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c index 9f0b2a5eadd..096e4712675 100644 --- a/gcc/tree-ssa-dom.c +++ b/gcc/tree-ssa-dom.c @@ -2291,11 +2291,16 @@ cprop_operand (gimple stmt, use_operand_p op_p) if (!may_propagate_copy (op, val)) return; - /* Do not propagate copies into simple IV increment statements. - See PR23821 for how this can disturb IV analysis. */ - if (TREE_CODE (val) != INTEGER_CST - && simple_iv_increment_p (stmt)) - return; + /* Do not propagate copies into BIVs. + See PR23821 and PR62217 for how this can disturb IV and + number of iteration analysis. */ + if (TREE_CODE (val) != INTEGER_CST) + { + gimple def = SSA_NAME_DEF_STMT (op); + if (gimple_code (def) == GIMPLE_PHI + && gimple_bb (def)->loop_father->header == gimple_bb (def)) + return; + } /* Dump details. */ if (dump_file && (dump_flags & TDF_DETAILS))