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| author | Diego Novillo <dnovillo@redhat.com> | 2004-07-28 17:57:27 +0000 |
|---|---|---|
| committer | Diego Novillo <dnovillo@gcc.gnu.org> | 2004-07-28 13:57:27 -0400 |
| commit | e0d3bb46f199dd0129bbe0df48cf6981610dbcef (patch) | |
| tree | 62decfb4fb7049220455e8e34566da59c3049bc2 | |
| parent | 852c7b12c56a25dfbad50418d9c4a093b7463bd4 (diff) | |
| download | gcc-e0d3bb46f199dd0129bbe0df48cf6981610dbcef.zip gcc-e0d3bb46f199dd0129bbe0df48cf6981610dbcef.tar.gz gcc-e0d3bb46f199dd0129bbe0df48cf6981610dbcef.tar.bz2 | |
tree-ssa-alias.c (maybe_create_global_var): Don't just return if .GLOBAL_VAR has been created.
* tree-ssa-alias.c (maybe_create_global_var): Don't just
return if .GLOBAL_VAR has been created.
From-SVN: r85268
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/tree-ssa-alias.c | 39 |
2 files changed, 25 insertions, 19 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 259ad7c..7341996 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,10 @@ 2004-07-28 Diego Novillo <dnovillo@redhat.com> + * tree-ssa-alias.c (maybe_create_global_var): Don't just + return if .GLOBAL_VAR has been created. + +2004-07-28 Diego Novillo <dnovillo@redhat.com> + * tree-ssa.c (verify_flow_insensitive_alias_info): Process every variable that may have aliases, not just tags. diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c index 94ccd80..7ad1867 100644 --- a/gcc/tree-ssa-alias.c +++ b/gcc/tree-ssa-alias.c @@ -1492,33 +1492,34 @@ maybe_create_global_var (struct alias_info *ai) size_t i, n_clobbered; /* No need to create it, if we have one already. */ - if (global_var) - return; - - /* Count all the call-clobbered variables. */ - n_clobbered = 0; - EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, i, n_clobbered++); + if (global_var == NULL_TREE) + { + /* Count all the call-clobbered variables. */ + n_clobbered = 0; + EXECUTE_IF_SET_IN_BITMAP (call_clobbered_vars, 0, i, n_clobbered++); - /* Create .GLOBAL_VAR if we have too many call-clobbered variables. - We also create .GLOBAL_VAR when there no call-clobbered variables - to prevent code motion transformations from re-arranging function - calls that may have side effects. For instance, + /* Create .GLOBAL_VAR if we have too many call-clobbered + variables. We also create .GLOBAL_VAR when there no + call-clobbered variables to prevent code motion + transformations from re-arranging function calls that may + have side effects. For instance, - foo () + foo () { int a = f (); g (); h (a); } - There are no call-clobbered variables in foo(), so it would be - entirely possible for a pass to want to move the call to f() - after the call to g(). If f() has side effects, that would be - wrong. Creating .GLOBAL_VAR in this case will insert VDEFs for - it and prevent such transformations. */ - if (n_clobbered == 0 - || ai->num_calls_found * n_clobbered >= (size_t) GLOBAL_VAR_THRESHOLD) - create_global_var (); + There are no call-clobbered variables in foo(), so it would + be entirely possible for a pass to want to move the call to + f() after the call to g(). If f() has side effects, that + would be wrong. Creating .GLOBAL_VAR in this case will + insert VDEFs for it and prevent such transformations. */ + if (n_clobbered == 0 + || ai->num_calls_found * n_clobbered >= (size_t) GLOBAL_VAR_THRESHOLD) + create_global_var (); + } /* If the function has calls to clobbering functions and .GLOBAL_VAR has been created, make it an alias for all call-clobbered variables. */ |