From 33bf2459e6cfe477a9be0c45aec3f6f359ee077c Mon Sep 17 00:00:00 2001
From: Mark Mendell <mark.p.mendell@intel.com>
Date: Wed, 27 May 2015 10:08:24 -0400
Subject: [PATCH] [optimizing] x86: Prefer add over lea if possible

Looking at some generated code, I noticed an lea being used when an add
was sufficient.  Check for that case, and generate the add.

Fixed for x86 and x86_64.

Change-Id: I110304ff0fed8837ada96d34353a293d29022ce5
Signed-off-by: Mark Mendell <mark.p.mendell@intel.com>
---
 compiler/optimizing/code_generator_x86.cc    | 2 ++
 compiler/optimizing/code_generator_x86_64.cc | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index a6f01dad3..597d27eb1 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -1959,6 +1959,8 @@ void InstructionCodeGeneratorX86::VisitAdd(HAdd* add) {
       if (second.IsRegister()) {
         if (out.AsRegister<Register>() == first.AsRegister<Register>()) {
           __ addl(out.AsRegister<Register>(), second.AsRegister<Register>());
+        } else if (out.AsRegister<Register>() == second.AsRegister<Register>()) {
+          __ addl(out.AsRegister<Register>(), first.AsRegister<Register>());
         } else {
           __ leal(out.AsRegister<Register>(), Address(
               first.AsRegister<Register>(), second.AsRegister<Register>(), TIMES_1, 0));
diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index f49c26db2..68e0065e6 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -2117,6 +2117,8 @@ void InstructionCodeGeneratorX86_64::VisitAdd(HAdd* add) {
       if (second.IsRegister()) {
         if (out.AsRegister<Register>() == first.AsRegister<Register>()) {
           __ addl(out.AsRegister<CpuRegister>(), second.AsRegister<CpuRegister>());
+        } else if (out.AsRegister<Register>() == second.AsRegister<Register>()) {
+          __ addl(out.AsRegister<CpuRegister>(), first.AsRegister<CpuRegister>());
         } else {
           __ leal(out.AsRegister<CpuRegister>(), Address(
               first.AsRegister<CpuRegister>(), second.AsRegister<CpuRegister>(), TIMES_1, 0));
@@ -2140,6 +2142,8 @@ void InstructionCodeGeneratorX86_64::VisitAdd(HAdd* add) {
       if (second.IsRegister()) {
         if (out.AsRegister<Register>() == first.AsRegister<Register>()) {
           __ addq(out.AsRegister<CpuRegister>(), second.AsRegister<CpuRegister>());
+        } else if (out.AsRegister<Register>() == second.AsRegister<Register>()) {
+          __ addq(out.AsRegister<CpuRegister>(), first.AsRegister<CpuRegister>());
         } else {
           __ leaq(out.AsRegister<CpuRegister>(), Address(
               first.AsRegister<CpuRegister>(), second.AsRegister<CpuRegister>(), TIMES_1, 0));
-- 
2.11.0