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| author | Richard Biener <rguenther@suse.de> | 2015-04-16 07:55:57 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2015-04-16 07:55:57 +0000 |
| commit | 8a474dc5d7d152653e90e960eff1852d1c7ff914 (patch) | |
| tree | 649c5ed590a9bcfcc0ac37c15b11b36688be346a /gcc/tree-ssa-ccp.c | |
| parent | 8d1cac076c9ac75a81f15e2249ff9a92a0278516 (diff) | |
| download | gcc-8a474dc5d7d152653e90e960eff1852d1c7ff914.zip gcc-8a474dc5d7d152653e90e960eff1852d1c7ff914.tar.gz gcc-8a474dc5d7d152653e90e960eff1852d1c7ff914.tar.bz2 | |
tree-ssa-ccp.c (likely_value): See if we have operands that are marked as never simulate again and return...
2015-04-16 Richard Biener <rguenther@suse.de>
* tree-ssa-ccp.c (likely_value): See if we have operands that
are marked as never simulate again and return CONSTANT in this
case.
* tree-ssa-propagate.c (simulate_stmt): Mark stmts that do
not have any operands that will be simulated again as
not being simulated again.
* gcc.dg/tree-ssa/ssa-ccp-36.c: New testcase.
* gcc.dg/tree-ssa/pr37508.c: Adjust.
* gfortran.dg/reassoc_6.f: Remove XFAIL.
From-SVN: r222141
Diffstat (limited to 'gcc/tree-ssa-ccp.c')
| -rw-r--r-- | gcc/tree-ssa-ccp.c | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c index eeae4bf..996296b 100644 --- a/gcc/tree-ssa-ccp.c +++ b/gcc/tree-ssa-ccp.c @@ -646,6 +646,7 @@ static ccp_lattice_t likely_value (gimple stmt) { bool has_constant_operand, has_undefined_operand, all_undefined_operands; + bool has_nsa_operand; tree use; ssa_op_iter iter; unsigned i; @@ -668,6 +669,7 @@ likely_value (gimple stmt) has_constant_operand = false; has_undefined_operand = false; all_undefined_operands = true; + has_nsa_operand = false; FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE) { ccp_prop_value_t *val = get_value (use); @@ -679,6 +681,10 @@ likely_value (gimple stmt) if (val->lattice_val == CONSTANT) has_constant_operand = true; + + if (SSA_NAME_IS_DEFAULT_DEF (use) + || !prop_simulate_again_p (SSA_NAME_DEF_STMT (use))) + has_nsa_operand = true; } /* There may be constants in regular rhs operands. For calls we @@ -751,8 +757,10 @@ likely_value (gimple stmt) /* We do not consider virtual operands here -- load from read-only memory may have only VARYING virtual operands, but still be - constant. */ + constant. Also we can combine the stmt with definitions from + operands whose definitions are not simulated again. */ if (has_constant_operand + || has_nsa_operand || gimple_references_memory_p (stmt)) return CONSTANT; |