8331090: Run Ideal_minmax before de-canonicalizing CMoves

[jaskarth]

Hi all, This patch aims to solve some CMove min/max patterns not being recognized due to the BoolNode comparison being non-canonical, as was reported in #18824. This can occur due to other Ideal transforms done by CMoves, such as in here and here. These transforms move constants and zero-types to the right hand side of the CMove by flipping the comparison, potentially de-canonicalizing it. These invariants are used later on in the ad files to emit more optimized assembly for these patterns. Since these existing patterns are useful to have, I think the best way to solve this would be to move Ideal_minmax before the branches are swapped and the BoolNode is negated. This should increase the set of inputs that the idealization is able to transform.

Tier 1-3 testing passes on my machine. Reviews and comments would be appreciated!

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Progress

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Issue

• JDK-8331090: Run Ideal_minmax before de-canonicalizing CMoves (Enhancement - P5)

Reviewers

• Tobias Hartmann (@TobiHartmann - Reviewer)

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[openjdk[bot]]

@jaskarth This change now passes all automated pre-integration checks.

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After integration, the commit message for the final commit will be:

8331090: Run Ideal_minmax before de-canonicalizing CMoves

Reviewed-by: thartmann, epeter

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At the time when this comment was updated there had been 428 new commits pushed to the master branch:

• a91f9ba84906dae10b050e15307ba0f0f05af3e4: 8301403: Eliminate memory allocations in JVMFlag::printFlags during signal handling
• 2c9fd9016f4675448a62380ff2b86533020e690f: 8336315: tools/jpackage/windows/WinChildProcessTest.java Failed: Check is calculator process is alive
• 1cb27f7e2355ccb911bb274fc004e5bc57fd5dc9: 8334230: Optimize C2 classes layout
• 41486131481164a559aa534807fe1a77a7d29fc8: 8335907: JFR: Make SettingControls more robust
• 79bdd811876d75974536aac088bae1719387c97f: 8336763: Parallel: Merge PCMarkAndPushClosure and PCIterateMarkAndPushClosure
• 8162832832ac6e8c17f942e718e309a3489e0da6: 8333354: ubsan: frame.inline.hpp:91:25: and src/hotspot/share/runtime/frame.inline.hpp:88:29: runtime error: member call on null pointer of type 'const struct SmallRegisterMap'
• 0325ab8d2353f29ac40ff4b028cbc29bff40c59b: 8335610: DiagnosticFramework: CmdLine::is_executable() correction
• 7ac531181c25815577ba2f6f426e1da270e4f589: 8331126: [s390x] secondary_super_cache does not scale well
• 156f0b4332bf076165898417cf6678d2fc32df5c: 8337213: Shenandoah: Add verification for class mirrors
• 9e6e0a8f341389215f0db6b2260f2b16351f02be: 8336343: Add more known sysroot library locations for ALSA
• ... and 418 more: https://git.openjdk.org/jdk/compare/93d98027649615afeeeb6a9510230d9655a74a8f...master

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• 00: Full (4918f26c)

[jaskarth]

Thank you for the review @TobiHartmann!

[TobiHartmann]

Testing passed. A second review would be good.

[eme64]

@TobiHartmann did you run performance benchmarking, just in case?

[eme64]

Just asking because we had some regressions recently around CMove ;)

[TobiHartmann]

No, I did not run any performance testing yet.

[eme64]

@TobiHartmann the testing looks clean.

[jaskarth]

Thanks for the testing and review @eme64!

/integrate

[openjdk[bot]]

Going to push as commit f2ba2ebbcaba2784b24e7fe94c235ca652f7c9a2. Since your change was applied there have been 442 commits pushed to the master branch:

• 7121d71b516b415c7c11e3643731cd32d4057aa6: 8337421: RISC-V: client VM build failure after JDK-8335191
• 61386c199a3b29457c002ad31a23990b7f6f88fd: 8337523: Fix -Wzero-as-null-pointer-constant warnings in jvmci code
• 07dd725025a54035436a76ac4c0a8bb2b12e264a: 8337418: Fix -Wzero-as-null-pointer-constant warnings in prims code
• c73b3cb5996723c5a15c833a9da059b79c99cf9c: 8336635: Add IR test for Reference.refersTo intrinsic
• 9b428dda8fb86ed595b05f3c930b3ce9c341db9b: 8336242: compiler/jvmci/jdk.vm.ci.code.test/src/jdk/vm/ci/code/test/SimpleDebugInfoTest.java failed assert(oopDesc::is_oop_or_null(val)) failed: bad oop found (again)
• de0b50400a4155554c83d5c3346ab1ec5353df61: 8336912: G1: Undefined behavior for G1ConfidencePercent=0
• e63d01654e0b702b3a8c0c4de97a6bb6893fbd1f: 8337031: Improvements to CompilationMemoryStatistic
• 1c6fef8f1cd12b26de9d31799a6516ce4399313f: 8337515: JVM_DumpAllStacks is dead code
• 5b7bb40d1f5a8e1261cc252db2a09b5e4f07e5f0: 8325002: Exceptions::fthrow needs to ensure it truncates to a valid utf8 string
• d39e7af2e5d28df43c0b2dad770f41adede5cc29: 8320561: Inconsistency in monitorinflation logging
• ... and 432 more: https://git.openjdk.org/jdk/compare/93d98027649615afeeeb6a9510230d9655a74a8f...master

Your commit was automatically rebased without conflicts.

[openjdk[bot]]

@jaskarth Pushed as commit f2ba2ebbcaba2784b24e7fe94c235ca652f7c9a2.

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