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| author | Richard Biener <rguenther@suse.de> | 2020-02-04 15:17:01 +0100 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2020-02-04 15:18:25 +0100 |
| commit | 5124c34fcc62f0f880ae947542678e28aa2ce703 (patch) | |
| tree | ed149fabf769e532c99a6fe6f1eecad4cafc740f | |
| parent | 9bc5bea1f3f0ce3927fd86ce728641d087f3d3b5 (diff) | |
| download | gcc-5124c34fcc62f0f880ae947542678e28aa2ce703.zip gcc-5124c34fcc62f0f880ae947542678e28aa2ce703.tar.gz gcc-5124c34fcc62f0f880ae947542678e28aa2ce703.tar.bz2 | |
tree-optimization/93538 - add missing comparison folding case
This adds back a folding that worked in GCC 4.5 times by amending
the pattern that handles other cases of address vs. SSA name
comparisons.
2020-02-04 Richard Biener <rguenther@suse.de>
PR tree-optimization/93538
* match.pd (addr EQ/NE ptr): Amend to handle &ptr->x EQ/NE ptr.
* gcc.dg/tree-ssa/forwprop-38.c: New testcase.
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/match.pd | 33 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/tree-ssa/forwprop-38.c | 13 |
4 files changed, 45 insertions, 11 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 04af968..d6b5ded 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,10 @@ 2020-02-04 Richard Biener <rguenther@suse.de> + PR tree-optimization/93538 + * match.pd (addr EQ/NE ptr): Amend to handle &ptr->x EQ/NE ptr. + +2020-02-04 Richard Biener <rguenther@suse.de> + PR tree-optimization/91123 * tree-ssa-sccvn.c (vn_walk_cb_data::finish): New method. (vn_walk_cb_data::last_vuse): New member. diff --git a/gcc/match.pd b/gcc/match.pd index 5fee394..73834c2 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -4267,19 +4267,30 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) { constant_boolean_node (above ? false : true, type); })))))))))))) (for cmp (eq ne) - /* A local variable can never be pointed to by - the default SSA name of an incoming parameter. - SSA names are canonicalized to 2nd place. */ (simplify + /* SSA names are canonicalized to 2nd place. */ (cmp addr@0 SSA_NAME@1) - (if (SSA_NAME_IS_DEFAULT_DEF (@1) - && TREE_CODE (SSA_NAME_VAR (@1)) == PARM_DECL) - (with { tree base = get_base_address (TREE_OPERAND (@0, 0)); } - (if (TREE_CODE (base) == VAR_DECL - && auto_var_in_fn_p (base, current_function_decl)) - (if (cmp == NE_EXPR) - { constant_boolean_node (true, type); } - { constant_boolean_node (false, type); })))))) + (with + { poly_int64 off; tree base; } + /* A local variable can never be pointed to by + the default SSA name of an incoming parameter. */ + (if (SSA_NAME_IS_DEFAULT_DEF (@1) + && TREE_CODE (SSA_NAME_VAR (@1)) == PARM_DECL + && (base = get_base_address (TREE_OPERAND (@0, 0))) + && TREE_CODE (base) == VAR_DECL + && auto_var_in_fn_p (base, current_function_decl)) + (if (cmp == NE_EXPR) + { constant_boolean_node (true, type); } + { constant_boolean_node (false, type); }) + /* If the address is based on @1 decide using the offset. */ + (if ((base = get_addr_base_and_unit_offset (TREE_OPERAND (@0, 0), &off)) + && TREE_CODE (base) == MEM_REF + && TREE_OPERAND (base, 0) == @1) + (with { off += mem_ref_offset (base).force_shwi (); } + (if (known_ne (off, 0)) + { constant_boolean_node (cmp == NE_EXPR, type); } + (if (known_eq (off, 0)) + { constant_boolean_node (cmp == EQ_EXPR, type); })))))))) /* Equality compare simplifications from fold_binary */ (for cmp (eq ne) diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 25e9595..7ce58af 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2020-02-04 Richard Biener <rguenther@suse.de> + + PR tree-optimization/93538 + * gcc.dg/tree-ssa/forwprop-38.c: New testcase. + 2020-02-04 Jakub Jelinek <jakub@redhat.com> * c-c++-common/cpp/has-include-1.c: New test. diff --git a/gcc/testsuite/gcc.dg/tree-ssa/forwprop-38.c b/gcc/testsuite/gcc.dg/tree-ssa/forwprop-38.c new file mode 100644 index 0000000..e016c82 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/forwprop-38.c @@ -0,0 +1,13 @@ +/* { dg-do compile } */ +/* { dg-options "-O -fdump-tree-forwprop1" } */ + +struct A { int a[1]; }; + +void f (struct A *p) +{ + void *q = p->a; + if (p != q) + __builtin_abort (); +} + +/* { dg-final { scan-tree-dump-not "abort" "forwprop1" } } */ |