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Differential D101636

[AArch64] Sets the preferred function alignment for Cortex-A53/A55
ClosedPublic

Authored by stelios-arm on Apr 30 2021, 7:57 AM.

Details

Reviewers
dmgreen
SjoerdMeijer
sanwou01
NickGuy
fhahn
Commits
rG36a44dfd95d8: [AArch64] Sets the preferred function alignment for Cortex-A53/A55.
Summary

Setting the preferred function alignment to 16 for Cortex A53/A55 improves performance in a wide range of benchmarks. This brings it in line with the
Cortex-A53/A55 tuning that is used in GCC (gcc/config/aarch64/aarch64.c).

Diff Detail

Event Timeline

stelios-arm created this revision.Apr 30 2021, 7:57 AM
Herald added subscribers: danielkiss, hiraditya, kristof.beyls. · View Herald TranscriptApr 30 2021, 7:57 AM
stelios-arm requested review of this revision.Apr 30 2021, 7:57 AM
Herald added a project: Restricted Project. · View Herald TranscriptApr 30 2021, 7:57 AM
Herald added a subscriber: llvm-commits. · View Herald Transcript
Harbormaster completed remote builds in B101931: Diff 341907.Apr 30 2021, 9:09 AM
SjoerdMeijer added a comment.EditedApr 30 2021, 9:40 AM

Just for completeness, I checked that GCC indeed sets it 16, here:

https://github.com/gcc-mirror/gcc/blob/71834be5b68e0c9839f0647e1bbf1eec4e4bbf49/gcc/config/aarch64/aarch64.c#L1277

Are we not adding tests for these kind of things?

dmgreen added a comment.Apr 30 2021, 9:54 AM

The test that needs updating is in CodeGen/AArch64/preferred-function-alignment.ll

stelios-arm updated this revision to Diff 341954.Apr 30 2021, 9:59 AM

Modified the Cortex-A53 test and added one for Cortex-A55.

Harbormaster completed remote builds in B101961: Diff 341954.Apr 30 2021, 11:49 AM
dmgreen accepted this revision.May 2 2021, 12:20 PM

Sounds good to me.

This revision is now accepted and ready to land.May 2 2021, 12:20 PM
Closed by commit rG36a44dfd95d8: [AArch64] Sets the preferred function alignment for Cortex-A53/A55. (authored by stelios-arm). · Explain WhyMay 2 2021, 4:00 PM
This revision was automatically updated to reflect the committed changes.
stelios-arm added a commit: rG36a44dfd95d8: [AArch64] Sets the preferred function alignment for Cortex-A53/A55..

Revision Contents

PathSize
llvm/
lib/
Target/
AArch64/
3 lines
test/
CodeGen/
AArch64/
3 lines

Diff 342289

llvm/lib/Target/AArch64/AArch64Subtarget.cpp

Show First 20 Lines • Show All 83 Lines • ▼ Show 20 Linesvoid AArch64Subtarget::initializeProperties() {
case Others: case Others:
break; break;
case Carmel: case Carmel:
CacheLineSize = 64; CacheLineSize = 64;
break; break;
case CortexA35: case CortexA35:
break; break;
case CortexA53: case CortexA53:
PrefFunctionLogAlignment = 3;
break;
case CortexA55: case CortexA55:
PrefFunctionLogAlignment = 4;
break; break;
case CortexA57: case CortexA57:
MaxInterleaveFactor = 4; MaxInterleaveFactor = 4;
PrefFunctionLogAlignment = 4; PrefFunctionLogAlignment = 4;
break; break;
case CortexA65: case CortexA65:
PrefFunctionLogAlignment = 3; PrefFunctionLogAlignment = 3;
break; break;
▲ Show 20 Lines • Show All 285 Lines • Show Last 20 Lines

llvm/test/CodeGen/AArch64/preferred-function-alignment.ll

; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=generic < %s | FileCheck --check-prefixes=ALIGN2,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=generic < %s | FileCheck --check-prefixes=ALIGN2,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a35 < %s | FileCheck --check-prefixes=ALIGN2,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a35 < %s | FileCheck --check-prefixes=ALIGN2,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a53 < %s | FileCheck --check-prefixes=ALIGN3,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a53 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a55 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a57 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a57 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a65 < %s | FileCheck --check-prefixes=ALIGN3,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a65 < %s | FileCheck --check-prefixes=ALIGN3,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a65ae < %s | FileCheck --check-prefixes=ALIGN3,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a65ae < %s | FileCheck --check-prefixes=ALIGN3,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a72 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a72 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a73 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a73 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a75 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a75 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a76 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=cortex-a76 < %s | FileCheck --check-prefixes=ALIGN4,CHECK %s
; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=a64fx < %s | FileCheck --check-prefixes=ALIGN3,CHECK %s ; RUN: llc -mtriple=aarch64-unknown-linux -mcpu=a64fx < %s | FileCheck --check-prefixes=ALIGN3,CHECK %s
Show All 30 Lines