diff options
Diffstat (limited to 'compiler/optimizing/instruction_simplifier_shared.cc')
| -rw-r--r-- | compiler/optimizing/instruction_simplifier_shared.cc | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/compiler/optimizing/instruction_simplifier_shared.cc b/compiler/optimizing/instruction_simplifier_shared.cc index 0f30f662cd..dc60ba62bb 100644 --- a/compiler/optimizing/instruction_simplifier_shared.cc +++ b/compiler/optimizing/instruction_simplifier_shared.cc @@ -336,4 +336,26 @@ bool TryExtractVecArrayAccessAddress(HVecMemoryOperation* access, HInstruction* return true; } +bool TryReplaceSubSubWithSubAdd(HSub* last_sub) { + DCHECK(last_sub->GetRight()->IsSub()); + HBasicBlock* basic_block = last_sub->GetBlock(); + ArenaAllocator* allocator = basic_block->GetGraph()->GetAllocator(); + HInstruction* last_sub_right = last_sub->GetRight(); + HInstruction* last_sub_left = last_sub->GetLeft(); + if (last_sub_right->GetUses().HasExactlyOneElement()) { + // Reorder operands of last_sub_right: Sub(a, b) -> Sub(b, a). + HInstruction* a = last_sub_right->InputAt(0); + HInstruction* b = last_sub_right->InputAt(1); + last_sub_right->ReplaceInput(b, 0); + last_sub_right->ReplaceInput(a, 1); + + // Replace Sub(c, Sub(a, b)) with Add(c, Sub(b, a). + HAdd* add = new (allocator) HAdd(last_sub->GetType(), last_sub_left, last_sub_right); + basic_block->ReplaceAndRemoveInstructionWith(last_sub, add); + return true; + } else { + return false; + } +} + } // namespace art |