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Differential D65766

[X86] Test the right bit to detect BMI2
ClosedPublic

Authored by atdt on Aug 5 2019, 11:34 AM.

Details

Reviewers
echristo
craig.topper
Commits
rGa93571098f50: Merging r367929: --------------------------------------------------------------…
rL367996: Merging r367929:
rG1d73e228db39: BMI2 support is indicated in bit eight of EBX, not nine. See Intel SDM, Vol 2A…
rL367929: BMI2 support is indicated in bit eight of EBX, not nine.
rCRT367929: BMI2 support is indicated in bit eight of EBX, not nine.
Summary

BMI2 support is indicated in bit eight of EBX, not nine.
See Intel SDM, Vol 2A, Table 3-8:
https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-vol-2a-manual.pdf#page=296

Diff Detail

Repository
rL LLVM

Event Timeline

atdt created this revision.Aug 5 2019, 11:34 AM
Herald added projects: Restricted Project, Restricted Project. · View Herald TranscriptAug 5 2019, 11:34 AM
Herald added subscribers: llvm-commits, Restricted Project. · View Herald Transcript
Harbormaster completed remote builds in B36157: Diff 213421.Aug 5 2019, 11:35 AM
atdt retitled this revision from Test the right bit to detect BMI2 to [X86] Test the right bit to detect BMI2.Aug 5 2019, 11:35 AM
atdt added a reviewer: echristo.
echristo accepted this revision.Aug 5 2019, 11:48 AM

This is fine. Can you add a link to the actual documentation in the commit message?

This revision is now accepted and ready to land.Aug 5 2019, 11:48 AM
craig.topper added a subscriber: craig.topper.Aug 5 2019, 11:58 AM

@atdt can you fix the copy of this code in llvm/lib/Support/Host.cpp as well?

atdt updated this revision to Diff 213430.Aug 5 2019, 12:17 PM

Fixed this in llvm/lib/Support/Host.cpp as well.

Herald added a subscriber: hiraditya. · View Herald TranscriptAug 5 2019, 12:17 PM
atdt edited the summary of this revision. (Show Details)Aug 5 2019, 12:18 PM
Harbormaster completed remote builds in B36161: Diff 213430.Aug 5 2019, 12:18 PM
craig.topper accepted this revision.Aug 5 2019, 12:23 PM

LGTM

xbolva00 added subscribers: hans, xbolva00.Aug 5 2019, 12:28 PM

Should be fixed in 9.0 too?

@hans

Closed by commit rL367929: BMI2 support is indicated in bit eight of EBX, not nine. (authored by echristo). · Explain WhyAug 5 2019, 2:25 PM
This revision was automatically updated to reflect the committed changes.
Herald added subscribers: kristina, delcypher. · View Herald TranscriptAug 5 2019, 2:25 PM
hans added a comment.Aug 6 2019, 1:25 AM
In D65766#1615458, @xbolva00 wrote:

Should be fixed in 9.0 too?

@hans

Merged to release_90 in r367996.

Revision Contents

PathSize
compiler-rt/
trunk/
lib/
builtins/
2 lines
llvm/
trunk/
lib/
Support/
2 lines

Diff 213464

compiler-rt/trunk/lib/builtins/cpu_model.c

Show First 20 Lines • Show All 537 Lines • ▼ Show 20 Lines#define setFeature(F) \
bool HasLeaf7 = bool HasLeaf7 =
MaxLeaf >= 0x7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX); MaxLeaf >= 0x7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
if (HasLeaf7 && ((EBX >> 3) & 1)) if (HasLeaf7 && ((EBX >> 3) & 1))
setFeature(FEATURE_BMI); setFeature(FEATURE_BMI);
if (HasLeaf7 && ((EBX >> 5) & 1) && HasAVX) if (HasLeaf7 && ((EBX >> 5) & 1) && HasAVX)
setFeature(FEATURE_AVX2); setFeature(FEATURE_AVX2);
if (HasLeaf7 && ((EBX >> 9) & 1)) if (HasLeaf7 && ((EBX >> 8) & 1))
setFeature(FEATURE_BMI2); setFeature(FEATURE_BMI2);
if (HasLeaf7 && ((EBX >> 16) & 1) && HasAVX512Save) if (HasLeaf7 && ((EBX >> 16) & 1) && HasAVX512Save)
setFeature(FEATURE_AVX512F); setFeature(FEATURE_AVX512F);
if (HasLeaf7 && ((EBX >> 17) & 1) && HasAVX512Save) if (HasLeaf7 && ((EBX >> 17) & 1) && HasAVX512Save)
setFeature(FEATURE_AVX512DQ); setFeature(FEATURE_AVX512DQ);
if (HasLeaf7 && ((EBX >> 21) & 1) && HasAVX512Save) if (HasLeaf7 && ((EBX >> 21) & 1) && HasAVX512Save)
setFeature(FEATURE_AVX512IFMA); setFeature(FEATURE_AVX512IFMA);
if (HasLeaf7 && ((EBX >> 26) & 1) && HasAVX512Save) if (HasLeaf7 && ((EBX >> 26) & 1) && HasAVX512Save)
▲ Show 20 Lines • Show All 135 Lines • Show Last 20 Lines

llvm/trunk/lib/Support/Host.cpp

Show First 20 Lines • Show All 1,028 Lines • ▼ Show 20 Linesstatic void getAvailableFeatures(unsigned ECX, unsigned EDX, unsigned MaxLeaf,
bool HasLeaf7 = bool HasLeaf7 =
MaxLeaf >= 0x7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX); MaxLeaf >= 0x7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
if (HasLeaf7 && ((EBX >> 3) & 1)) if (HasLeaf7 && ((EBX >> 3) & 1))
setFeature(X86::FEATURE_BMI); setFeature(X86::FEATURE_BMI);
if (HasLeaf7 && ((EBX >> 5) & 1) && HasAVX) if (HasLeaf7 && ((EBX >> 5) & 1) && HasAVX)
setFeature(X86::FEATURE_AVX2); setFeature(X86::FEATURE_AVX2);
if (HasLeaf7 && ((EBX >> 9) & 1)) if (HasLeaf7 && ((EBX >> 8) & 1))
setFeature(X86::FEATURE_BMI2); setFeature(X86::FEATURE_BMI2);
if (HasLeaf7 && ((EBX >> 16) & 1) && HasAVX512Save) if (HasLeaf7 && ((EBX >> 16) & 1) && HasAVX512Save)
setFeature(X86::FEATURE_AVX512F); setFeature(X86::FEATURE_AVX512F);
if (HasLeaf7 && ((EBX >> 17) & 1) && HasAVX512Save) if (HasLeaf7 && ((EBX >> 17) & 1) && HasAVX512Save)
setFeature(X86::FEATURE_AVX512DQ); setFeature(X86::FEATURE_AVX512DQ);
if (HasLeaf7 && ((EBX >> 19) & 1)) if (HasLeaf7 && ((EBX >> 19) & 1))
setFeature(X86::FEATURE_ADX); setFeature(X86::FEATURE_ADX);
if (HasLeaf7 && ((EBX >> 21) & 1) && HasAVX512Save) if (HasLeaf7 && ((EBX >> 21) & 1) && HasAVX512Save)
▲ Show 20 Lines • Show All 471 Lines • Show Last 20 Lines