Adds `ccmp` logic into emitter backend. #112153

anthonycanino · 2025-02-04T21:20:36Z

Overview

This PR adds APX new ccmp instruction to the X86 backend.

Design

For reference, there is a unique extended evex encoding for ccmp:

where SC0 - SC3 encode the condition for ccmp to conditionally execute on (please see SDM Vol 1, Appendix B). If the status codes fail to satisfy the condition encoded by SC0 - SC3, no compare will be performed, and the OF, SF, ZF, and CF flags will be set to the default flag value (DFV) fields of, sf, zf and cf.

Testing

Note: The testing plan for APX work has been discussed in #106557, please refer to that PR for details, only results and comments will be posted in this PR. Results

anthonycanino · 2025-02-04T21:21:08Z

1. Emitter unit tests

The left is output from JitDisasm, and right from JitLateDisasm.

2. Intel SDE testing

Test run with SDE:

3. SuperPMI results

Diffs are based on 2,623,457 contexts (1,043,127 MinOpts, 1,580,330 FullOpts).

MISSED contexts: 2,983 (0.11%)

Base JIT options: JitBypassApxCheck=1

Diff JIT options: JitBypassApxCheck=1

No diffs found.

Details

Context information

Collection	Diffed contexts	MinOpts	FullOpts	Missed, base	Missed, diff
aspnet.run.windows.x64.checked.mch	126,540	63,098	63,442	2,665 (2.06%)	2,665 (2.06%)
benchmarks.run.windows.x64.checked.mch	28,757	4	28,753	0 (0.00%)	0 (0.00%)
benchmarks.run_pgo.windows.x64.checked.mch	105,618	52,679	52,939	0 (0.00%)	0 (0.00%)
benchmarks.run_tiered.windows.x64.checked.mch	55,912	38,403	17,509	0 (0.00%)	0 (0.00%)
coreclr_tests.run.windows.x64.checked.mch	582,221	349,625	232,596	0 (0.00%)	0 (0.00%)
libraries.crossgen2.windows.x64.checked.mch	280,377	16	280,361	0 (0.00%)	0 (0.00%)
libraries.pmi.windows.x64.checked.mch	295,086	6	295,080	0 (0.00%)	0 (0.00%)
libraries_tests.run.windows.x64.Release.mch	751,895	517,237	234,658	0 (0.00%)	0 (0.00%)
libraries_tests_no_tiered_compilation.run.windows.x64.Release.mch	342,818	22,045	320,773	0 (0.00%)	0 (0.00%)
realworld.run.windows.x64.checked.mch	24,824	2	24,822	0 (0.00%)	0 (0.00%)
smoke_tests.nativeaot.windows.x64.checked.mch	29,409	12	29,397	318 (1.07%)	318 (1.07%)
	2,623,457	1,043,127	1,580,330	2,983 (0.11%)	2,983 (0.11%)

dotnet-policy-service · 2025-02-04T21:21:11Z

Tagging subscribers to this area: @JulieLeeMSFT, @jakobbotsch
See info in area-owners.md if you want to be subscribed.

anthonycanino · 2025-02-10T22:50:07Z

I believe failures are related to #112163

anthonycanino · 2025-02-12T17:40:10Z

@dotnet/jit-contrib could we get this looked at for a review to see if any changes are needed?

JulieLeeMSFT · 2025-02-12T19:15:19Z

CC @amanasifkhalid and @EgorBo for code review.

EgorBo · 2025-02-12T22:13:05Z

Do you have any idea why it shows up to 0.36% TP regression? Presumably, it's supposed to be zero-diff change?

amanasifkhalid · 2025-02-13T19:04:38Z

Do you have any idea why it shows up to 0.36% TP regression? Presumably, it's supposed to be zero-diff change?

The insOpts enum now has entries that are larger than a byte -- perhaps the native compilers were previously compacting the enum (though that doesn't sound like a valid transformation)? Nothing else really sticks out to me.

anthonycanino · 2025-02-13T22:10:53Z

There are a few places where SetDFVIfNeeded is called, particularly in emitInsRR that would have an additional if statement check. That's probably what it is.

We could adjust it so it only triggers for TARGET_AMD64 and not TARGET_X86. It currently follows the same precedent as SetNFIfNeeded etc.

BruceForstall

It would be nice to reduce the TP impact if possible. If this doesn't apply to x86, definitely make SetDFVIfNeeded() ifdef'ed for AMD64 (maybe create an empty function for x86 so call sites don't change). The full TP impact is only on MinOpts, fwiw.

BruceForstall · 2025-02-14T00:21:17Z

src/coreclr/jit/emit.h

+            _idCustom2 = ((value >> 1) & 1);
+            _idCustom3 = ((value >> 2) & 1);
+            _idCustom4 = ((value >> 3) & 1);
+        }


Consider adding:

assert(value == idGetEvexDFV());

BruceForstall · 2025-02-14T00:30:24Z

src/coreclr/jit/codegenxarch.cpp

+    emitter* theEmitter = GetEmitter();
+    genDefineTempLabel(genCreateTempLabel());
+
+    // #ifdef COMMENTOUT


BruceForstall · 2025-02-14T00:30:31Z

src/coreclr/jit/codegenxarch.cpp

+    CORINFO_FIELD_HANDLE hnd = theEmitter->emitFltOrDblConst(1.0f, EA_4BYTE);
+    theEmitter->emitIns_R_C(INS_ccmpe, EA_4BYTE, REG_RAX, hnd, 0, INS_OPTS_EVEX_dfv_cf);
+    theEmitter->emitIns_R_C(INS_ccmpe, EA_4BYTE, REG_RAX, hnd, 4, INS_OPTS_EVEX_dfv_cf);
+    // #endif


anthonycanino · 2025-02-14T23:32:40Z

FYI throughput impact removed on x86 https://dev.azure.com/dnceng-public/public/_build/results?buildId=953002&view=ms.vss-build-web.run-extensions-tab

* main: (71 commits) Update dependencies from https://github.com/dotnet/source-build-reference-packages build 20250212.3 (dotnet#112626) JIT: Unify struct arg morphing (dotnet#112612) Enable `SA1015`: Closing generic bracket should not be followed by a space (dotnet#112597) Clean up normalizeLocale for mono browser target (dotnet#112575) SPMI: Ensure proper zero extension for isObjectImmutable and friends (dotnet#112617) Quote --version-scripts path (dotnet#112603) Remove incompatible API from PKCS netstandard2.0 lib [main] Update dependencies from dotnet/emsdk (dotnet#112393) Avoid `Unsafe.As` in `RangeCharSearchValues` (dotnet#112606) Fixed the issue of incorrect return value of PalVirtualAlloc (dotnet#112579) Fix size used for vectorization check in BitArray (dotnet#111558) (dotnet#111564) Fix build of windows arm64 crossdac (dotnet#112553) Simplify `ShuffleTakeIterator.GetCount` (dotnet#112593) Fix VS div-by-0 in DacEnumerableHashTable code (dotnet#112542) R2RDump: normalize GC info totalInterruptibleLength (dotnet#112003) Fix alignment padding and add test for saving managed resources (dotnet#110915) Adds `ccmp` logic into emitter backend. (dotnet#112153) Disable AVX10.2 by default (dotnet#112572) Outbox AesGcm in to Microsoft.Bcl.Cryptography Make test `IUnknown` conforming (dotnet#112566) ...

dotnet-issue-labeler bot added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Feb 4, 2025

dotnet-policy-service bot added the community-contribution Indicates that the PR has been added by a community member label Feb 4, 2025

build-analysis bot mentioned this pull request Feb 5, 2025

The Operation will be canceled. The next steps may not contain expected logs. dotnet/dnceng#3008

Open

3 tasks

anthonycanino force-pushed the apx-ccmp branch from c8459bb to 3f154a9 Compare February 10, 2025 17:34

build-analysis bot mentioned this pull request Feb 11, 2025

slow macOS - "##[error]The job running on agent Azure Pipelines 9 ran longer than the maximum time of 60 minutes." dotnet/dnceng#1883

Open

3 tasks

JulieLeeMSFT added this to the 10.0.0 milestone Feb 12, 2025

JulieLeeMSFT assigned anthonycanino Feb 12, 2025

JulieLeeMSFT requested review from EgorBo and amanasifkhalid February 12, 2025 19:15

BruceForstall reviewed Feb 14, 2025

View reviewed changes

Adds ccmp logic into emitter backend.

1c03537

anthonycanino force-pushed the apx-ccmp branch from 3f154a9 to f0e0b7e Compare February 14, 2025 18:42

Review edits

2e9ecb6

anthonycanino force-pushed the apx-ccmp branch from f0e0b7e to 2e9ecb6 Compare February 14, 2025 18:58

Small fix.

afb99d5

BruceForstall approved these changes Feb 15, 2025

View reviewed changes

BruceForstall merged commit 01e4d44 into dotnet:main Feb 15, 2025
112 checks passed

BruceForstall added the apx Related to the Intel Advanced Performance Extensions (APX) label Feb 15, 2025

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Adds `ccmp` logic into emitter backend. #112153

Adds `ccmp` logic into emitter backend. #112153

anthonycanino commented Feb 4, 2025

anthonycanino commented Feb 4, 2025

Context information

dotnet-policy-service bot commented Feb 4, 2025

anthonycanino commented Feb 10, 2025

anthonycanino commented Feb 12, 2025

JulieLeeMSFT commented Feb 12, 2025

EgorBo commented Feb 12, 2025 •

edited

Loading

amanasifkhalid commented Feb 13, 2025 •

edited

Loading

anthonycanino commented Feb 13, 2025 •

edited

Loading

BruceForstall left a comment

BruceForstall Feb 14, 2025

BruceForstall Feb 14, 2025

BruceForstall Feb 14, 2025

anthonycanino commented Feb 14, 2025

Adds ccmp logic into emitter backend. #112153

Adds ccmp logic into emitter backend. #112153

Conversation

anthonycanino commented Feb 4, 2025

Overview

Design

Testing

anthonycanino commented Feb 4, 2025

1. Emitter unit tests

2. Intel SDE testing

3. SuperPMI results

Context information

dotnet-policy-service bot commented Feb 4, 2025

anthonycanino commented Feb 10, 2025

anthonycanino commented Feb 12, 2025

JulieLeeMSFT commented Feb 12, 2025

EgorBo commented Feb 12, 2025 • edited Loading

amanasifkhalid commented Feb 13, 2025 • edited Loading

anthonycanino commented Feb 13, 2025 • edited Loading

BruceForstall left a comment

Choose a reason for hiding this comment

BruceForstall Feb 14, 2025

Choose a reason for hiding this comment

BruceForstall Feb 14, 2025

Choose a reason for hiding this comment

BruceForstall Feb 14, 2025

Choose a reason for hiding this comment

anthonycanino commented Feb 14, 2025

Adds `ccmp` logic into emitter backend. #112153

Adds `ccmp` logic into emitter backend. #112153

EgorBo commented Feb 12, 2025 •

edited

Loading

amanasifkhalid commented Feb 13, 2025 •

edited

Loading

anthonycanino commented Feb 13, 2025 •

edited

Loading