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| author | Richard Biener <rguenther@suse.de> | 2018-11-20 09:31:06 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2018-11-20 09:31:06 +0000 |
| commit | dc3221e1e3d3a39d88d2d35103f6f50e3400d7a8 (patch) | |
| tree | da4944c9019f08cbd4e0f94ce31956af82630d92 /gcc | |
| parent | 643427d70f7a547a1db8a8492a6a124ff22c0d3a (diff) | |
| download | gcc-dc3221e1e3d3a39d88d2d35103f6f50e3400d7a8.zip gcc-dc3221e1e3d3a39d88d2d35103f6f50e3400d7a8.tar.gz gcc-dc3221e1e3d3a39d88d2d35103f6f50e3400d7a8.tar.bz2 | |
re PR middle-end/83215 (C++: struct with char-array assumed to alias with everything)
2018-11-20 Richard Biener <rguenther@suse.de>
PR middle-end/83215
* alias.c (component_uses_parent_alias_set_from): Remove
alias-set zero and TYPE_TYPELESS_STORAGE case both already
handled in other ways.
* g++.dg/tree-ssa/pr83215.C: New testcase.
From-SVN: r266305
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/alias.c | 10 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/tree-ssa/pr83215.C | 19 |
4 files changed, 32 insertions, 9 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index affdfd6..ee2d87d 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,12 @@ 2018-11-20 Richard Biener <rguenther@suse.de> + PR middle-end/83215 + * alias.c (component_uses_parent_alias_set_from): Remove + alias-set zero and TYPE_TYPELESS_STORAGE case both already + handled in other ways. + +2018-11-20 Richard Biener <rguenther@suse.de> + PR tree-optimization/88087 * tree-ssa-pre.c (create_expression_by_pieces): Re-materialize call fntype. diff --git a/gcc/alias.c b/gcc/alias.c index 7963ece..835ac82 100644 --- a/gcc/alias.c +++ b/gcc/alias.c @@ -601,8 +601,7 @@ objects_must_conflict_p (tree t1, tree t2) /* Return the outermost parent of component present in the chain of component references handled by get_inner_reference in T with the following property: - - the component is non-addressable, or - - the parent has alias set zero, + - the component is non-addressable or NULL_TREE if no such parent exists. In the former cases, the alias set of this parent is the alias set that must be used for T itself. */ @@ -611,10 +610,6 @@ component_uses_parent_alias_set_from (const_tree t) { const_tree found = NULL_TREE; - if (AGGREGATE_TYPE_P (TREE_TYPE (t)) - && TYPE_TYPELESS_STORAGE (TREE_TYPE (t))) - return const_cast <tree> (t); - while (handled_component_p (t)) { switch (TREE_CODE (t)) @@ -652,9 +647,6 @@ component_uses_parent_alias_set_from (const_tree t) gcc_unreachable (); } - if (get_alias_set (TREE_TYPE (TREE_OPERAND (t, 0))) == 0) - found = t; - t = TREE_OPERAND (t, 0); } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e378047..31540b5 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2018-11-20 Richard Biener <rguenther@suse.de> + + PR middle-end/83215 + * g++.dg/tree-ssa/pr83215.C: New testcase. + 2018-11-20 Eric Botcazou <ebotcazou@adacore.com> * gcc.c-torture/execute/20181120-1.c: New test. diff --git a/gcc/testsuite/g++.dg/tree-ssa/pr83215.C b/gcc/testsuite/g++.dg/tree-ssa/pr83215.C new file mode 100644 index 0000000..d21ac46 --- /dev/null +++ b/gcc/testsuite/g++.dg/tree-ssa/pr83215.C @@ -0,0 +1,19 @@ +// { dg-do compile } +// { dg-options "-O2 -fdump-tree-fre1" } + +struct mytest +{ + float a; + char buf[256]; +}; + +int foo(mytest *m, int *i) +{ + int tmp = *i; + m->a = 10.0f; + return tmp + *i; +} + +// we should be able to CSE *i despite mytest having a cbar[] buffer +// and thus being subject to TYPE_TYPELESS_STORAGE +// { dg-final { scan-tree-dump-times "\\*i" 1 "fre1" } } |