Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(149)

Unified Diff: src/x64/macro-assembler-x64.h

Issue 23654026: Use xorps to break the cvtsi2sd unnecessary dependence due to its partially written (Closed) Base URL: git://github.com/v8/v8.git@master
Patch Set: rebase to master and address comments Created 7 years, 3 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « src/x64/lithium-codegen-x64.cc ('k') | src/x64/macro-assembler-x64.cc » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: src/x64/macro-assembler-x64.h
diff --git a/src/x64/macro-assembler-x64.h b/src/x64/macro-assembler-x64.h
index 09c8a800ccab1a4e3cdf06a7337dc0c2284b6efc..a1b04d55df7d59bfc576b0df692fce1c990d5cf2 100644
--- a/src/x64/macro-assembler-x64.h
+++ b/src/x64/macro-assembler-x64.h
@@ -784,6 +784,12 @@ class MacroAssembler: public Assembler {
void Set(Register dst, int64_t x);
void Set(const Operand& dst, int64_t x);
+ // cvtsi2sd instruction only writes to the low 64-bit of dst register, which
+ // hinders register renaming and makes dependence chains longer. So we use
+ // xorps to clear the dst register before cvtsi2sd to solve this issue.
+ void Cvtlsi2sd(XMMRegister dst, Register src);
+ void Cvtlsi2sd(XMMRegister dst, const Operand& src);
+
// Move if the registers are not identical.
void Move(Register target, Register source);
« no previous file with comments | « src/x64/lithium-codegen-x64.cc ('k') | src/x64/macro-assembler-x64.cc » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698