diff options
| -rw-r--r-- | gcc/ChangeLog | 10 | ||||
| -rw-r--r-- | gcc/fold-const.c | 18 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 4 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/tree-ssa/fwprop-align.C | 20 | ||||
| -rw-r--r-- | gcc/tree-ssa-forwprop.c | 52 |
5 files changed, 99 insertions, 5 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index fcbe897..a977546 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2009-03-28 Martin Jambor <mjambor@suse.cz> + + * fold-const.c (get_pointer_modulus_and_residue): New parameter + allow_func_align. + (fold_binary): Allow function decl aligment consideration is the + second argument is integer constant one. + * tree-ssa-forwprop.c (simplify_bitwise_and): New function. + (tree_ssa_forward_propagate_single_use_vars): Handle assing statements + with BIT_AND_EXPR on the RHS by calling simplify_bitwise_and. + 2009-03-28 Jan Hubicka <jh@suse.cz> * dwarf2out.c (dwarf2out_begin_prologue): Use crtl->nothrow diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 2dbca3f..a68b7b8 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -9551,10 +9551,15 @@ fold_mult_zconjz (tree type, tree expr) 0 <= N < M as is common. In general, the precise value of P is unknown. M is chosen as large as possible such that constant N can be determined. - Returns M and sets *RESIDUE to N. */ + Returns M and sets *RESIDUE to N. + + If ALLOW_FUNC_ALIGN is true, do take functions' DECL_ALIGN_UNIT into + account. This is not always possible due to PR 35705. + */ static unsigned HOST_WIDE_INT -get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue) +get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue, + bool allow_func_align) { enum tree_code code; @@ -9584,7 +9589,8 @@ get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue) } } - if (DECL_P (expr) && TREE_CODE (expr) != FUNCTION_DECL) + if (DECL_P (expr) + && (allow_func_align || TREE_CODE (expr) != FUNCTION_DECL)) return DECL_ALIGN_UNIT (expr); } else if (code == POINTER_PLUS_EXPR) @@ -9595,7 +9601,8 @@ get_pointer_modulus_and_residue (tree expr, unsigned HOST_WIDE_INT *residue) op0 = TREE_OPERAND (expr, 0); STRIP_NOPS (op0); - modulus = get_pointer_modulus_and_residue (op0, residue); + modulus = get_pointer_modulus_and_residue (op0, residue, + allow_func_align); op1 = TREE_OPERAND (expr, 1); STRIP_NOPS (op1); @@ -11235,7 +11242,8 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1) unsigned HOST_WIDE_INT modulus, residue; unsigned HOST_WIDE_INT low = TREE_INT_CST_LOW (arg1); - modulus = get_pointer_modulus_and_residue (arg0, &residue); + modulus = get_pointer_modulus_and_residue (arg0, &residue, + integer_onep (arg1)); /* This works because modulus is a power of 2. If this weren't the case, we'd have to replace it by its greatest power-of-2 diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 4f7b111..467691c 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2009-03-28 Martin Jambor <mjambor@suse.cz> + + * g++.dg/tree-ssa/fwprop-align.C: New test. + 2009-03-28 Jakub Jelinek <jakub@redhat.com> * gcc.target/powerpc/altivec-28.c: New test. diff --git a/gcc/testsuite/g++.dg/tree-ssa/fwprop-align.C b/gcc/testsuite/g++.dg/tree-ssa/fwprop-align.C new file mode 100644 index 0000000..69f2602 --- /dev/null +++ b/gcc/testsuite/g++.dg/tree-ssa/fwprop-align.C @@ -0,0 +1,20 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-forwprop2" } */ + +struct A +{ + void foo () + { + } +}; + +int main() +{ + void (A::* const p)() = & A::foo; + A a; + (a.*p)(); +} + +/* We should eliminate the check if p points to a virtual function. */ +/* { dg-final { scan-tree-dump-times "& 1" 0 "forwprop2" } } */ +/* { dg-final { cleanup-tree-dump "forwprop2" } } */ diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c index dd45bb7..fb29f91 100644 --- a/gcc/tree-ssa-forwprop.c +++ b/gcc/tree-ssa-forwprop.c @@ -147,6 +147,14 @@ along with GCC; see the file COPYING3. If not see ptr2 = &x[index]; + Or + ssa = (int) decl + res = ssa & 1 + + Provided that decl has known alignment >= 2, will get turned into + + res = 0 + We also propagate casts into SWITCH_EXPR and COND_EXPR conditions to allow us to remove the cast and {NOT_EXPR,NEG_EXPR} into a subsequent {NOT_EXPR,NEG_EXPR}. @@ -1124,6 +1132,45 @@ simplify_gimple_switch (gimple stmt) } } +/* Run bitwise and assignments throug the folder. If the first argument is an + ssa name that is itself a result of a typecast of an ADDR_EXPR to an + integer, feed the ADDR_EXPR to the folder rather than the ssa name. +*/ + +static void +simplify_bitwise_and (gimple_stmt_iterator *gsi, gimple stmt) +{ + tree res; + tree arg1 = gimple_assign_rhs1 (stmt); + tree arg2 = gimple_assign_rhs2 (stmt); + + if (TREE_CODE (arg2) != INTEGER_CST) + return; + + if (TREE_CODE (arg1) == SSA_NAME && !SSA_NAME_IS_DEFAULT_DEF (arg1)) + { + gimple def = SSA_NAME_DEF_STMT (arg1); + + if (gimple_assign_cast_p (def) + && INTEGRAL_TYPE_P (gimple_expr_type (def))) + { + tree op = gimple_assign_rhs1 (def); + + if (TREE_CODE (op) == ADDR_EXPR) + arg1 = op; + } + } + + res = fold_binary (BIT_AND_EXPR, TREE_TYPE (gimple_assign_lhs (stmt)), + arg1, arg2); + if (res && is_gimple_min_invariant (res)) + { + gimple_assign_set_rhs_from_tree (gsi, res); + update_stmt (stmt); + } + return; +} + /* Main entry point for the forward propagation optimizer. */ static unsigned int @@ -1206,6 +1253,11 @@ tree_ssa_forward_propagate_single_use_vars (void) else gsi_next (&gsi); } + else if (gimple_assign_rhs_code (stmt) == BIT_AND_EXPR) + { + simplify_bitwise_and (&gsi, stmt); + gsi_next (&gsi); + } else gsi_next (&gsi); } |