From 8024d4b6c9ce06d63a87788c7fd4f74461552227 Mon Sep 17 00:00:00 2001 From: Tom de Vries Date: Wed, 19 Nov 2014 10:44:58 +0000 Subject: [PATCH] Fix tail-merge pass for dead type-unsafe code 2014-11-19 Tom de Vries PR tree-optimization/62167 * tree-ssa-tail-merge.c (stmt_local_def): Handle statements with vuse conservatively. (gimple_equal_p): Don't use vn_valueize to compare for lhs equality of assigns. * gcc.dg/pr51879-12.c: Add xfails. * gcc.dg/pr62167-run.c: New test. * gcc.dg/pr62167.c: New test. From-SVN: r217761 --- gcc/ChangeLog | 8 +++++ gcc/testsuite/ChangeLog | 7 +++++ gcc/testsuite/gcc.dg/pr51879-12.c | 4 +-- gcc/testsuite/gcc.dg/pr62167-run.c | 47 ++++++++++++++++++++++++++++ gcc/testsuite/gcc.dg/pr62167.c | 50 ++++++++++++++++++++++++++++++ gcc/tree-ssa-tail-merge.c | 6 ++-- 6 files changed, 118 insertions(+), 4 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/pr62167-run.c create mode 100644 gcc/testsuite/gcc.dg/pr62167.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index ff9fe1e8b57..9169e354e8e 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2014-11-19 Tom de Vries + + PR tree-optimization/62167 + * tree-ssa-tail-merge.c (stmt_local_def): Handle statements with vuse + conservatively. + (gimple_equal_p): Don't use vn_valueize to compare for lhs equality of + assigns. + 2014-11-19 Jakub Jelinek PR tree-optimization/63915 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 08a6c234acc..35cb09ce4d3 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,10 @@ +2014-11-19 Tom de Vries + + PR tree-optimization/62167 + * gcc.dg/pr51879-12.c: Add xfails. + * gcc.dg/pr62167-run.c: New test. + * gcc.dg/pr62167.c: New test. + 2014-11-19 Jakub Jelinek PR tree-optimization/63915 diff --git a/gcc/testsuite/gcc.dg/pr51879-12.c b/gcc/testsuite/gcc.dg/pr51879-12.c index 8126505f384..85e2687da17 100644 --- a/gcc/testsuite/gcc.dg/pr51879-12.c +++ b/gcc/testsuite/gcc.dg/pr51879-12.c @@ -24,6 +24,6 @@ foo (int y) baz (a); } -/* { dg-final { scan-tree-dump-times "bar \\(" 1 "pre"} } */ -/* { dg-final { scan-tree-dump-times "bar2 \\(" 1 "pre"} } */ +/* { dg-final { scan-tree-dump-times "bar \\(" 1 "pre" { xfail *-*-* } } } */ +/* { dg-final { scan-tree-dump-times "bar2 \\(" 1 "pre" { xfail *-*-* } } } */ /* { dg-final { cleanup-tree-dump "pre" } } */ diff --git a/gcc/testsuite/gcc.dg/pr62167-run.c b/gcc/testsuite/gcc.dg/pr62167-run.c new file mode 100644 index 00000000000..37214a3ecee --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr62167-run.c @@ -0,0 +1,47 @@ +/* { dg-do run } */ +/* { dg-options "-O2 -ftree-tail-merge" } */ + +struct node +{ + struct node *next; + struct node *prev; +}; + +struct node node; + +struct head +{ + struct node *first; +}; + +struct head heads[5]; + +int k = 2; + +struct head *head = &heads[2]; + +int +main () +{ + struct node *p; + + node.next = (void*)0; + + node.prev = (void *)head; + + head->first = &node; + + struct node *n = head->first; + + struct head *h = &heads[k]; + + heads[2].first = n->next; + + if ((void*)n->prev == (void *)h) + p = h->first; + else + /* Dead tbaa-unsafe load from ((struct node *)&heads[2])->next. */ + p = n->prev->next; + + return !(p == (void*)0); +} diff --git a/gcc/testsuite/gcc.dg/pr62167.c b/gcc/testsuite/gcc.dg/pr62167.c new file mode 100644 index 00000000000..f8c31a0792f --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr62167.c @@ -0,0 +1,50 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -ftree-tail-merge -fdump-tree-pre" } */ + +struct node +{ + struct node *next; + struct node *prev; +}; + +struct node node; + +struct head +{ + struct node *first; +}; + +struct head heads[5]; + +int k = 2; + +struct head *head = &heads[2]; + +int +main () +{ + struct node *p; + + node.next = (void*)0; + + node.prev = (void *)head; + + head->first = &node; + + struct node *n = head->first; + + struct head *h = &heads[k]; + + heads[2].first = n->next; + + if ((void*)n->prev == (void *)h) + p = h->first; + else + /* Dead tbaa-unsafe load from ((struct node *)&heads[2])->next. */ + p = n->prev->next; + + return !(p == (void*)0); +} + +/* { dg-final { scan-tree-dump-not "Removing basic block" "pre"} } */ +/* { dg-final { cleanup-tree-dump "pre" } } */ diff --git a/gcc/tree-ssa-tail-merge.c b/gcc/tree-ssa-tail-merge.c index 303bd5e4c4a..16519853b0e 100644 --- a/gcc/tree-ssa-tail-merge.c +++ b/gcc/tree-ssa-tail-merge.c @@ -326,7 +326,8 @@ stmt_local_def (gimple stmt) if (gimple_vdef (stmt) != NULL_TREE || gimple_has_side_effects (stmt) - || gimple_could_trap_p_1 (stmt, false, false)) + || gimple_could_trap_p_1 (stmt, false, false) + || gimple_vuse (stmt) != NULL_TREE) return false; def_p = SINGLE_SSA_DEF_OPERAND (stmt, SSA_OP_DEF); @@ -1175,7 +1176,8 @@ gimple_equal_p (same_succ same_succ, gimple s1, gimple s2) gimple_assign_rhs1 (s2))); else if (TREE_CODE (lhs1) == SSA_NAME && TREE_CODE (lhs2) == SSA_NAME) - return vn_valueize (lhs1) == vn_valueize (lhs2); + return operand_equal_p (gimple_assign_rhs1 (s1), + gimple_assign_rhs1 (s2), 0); return false; case GIMPLE_COND: -- 2.30.2