pre-commit: PR165748 #3012
pre-commit: PR165748 #3012
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Diff moderunner: ariselab-64c-docker 1584 files changed, 565768 insertions(+), 566738 deletions(-) +9 wasmtime-rs/5079e95b7v1wxko.ll |
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Here is a summary of the major changes in the provided patch:
These changes collectively improve code clarity, correctness, and optimization potential by simplifying control flow, removing dead paths, and enhancing memory operation semantics. model: qwen-plus-latest |
…n of conditions (#165748) In simplifycfg/cvp/sccp, we eliminate dead edges of switches according to the knownbits/range info of conditions. However, these approximations may not meet the real-world needs when the domain of condition values is sparse. For example, if the condition can only be either -3 or 3, we cannot prove that the condition never evaluates to 1 (knownbits: ???????1, range: [-3, 4)). This patch adds a helper function `collectPossibleValues` to enumerate all the possible values of V. To fix the motivating issue, `eliminateDeadSwitchCases` will use the result to remove dead edges. Note: In https://discourse.llvm.org/t/missed-optimization-due-to-overflow-check/88700 I proposed a new value lattice kind to represent such values. But I find it hard to apply because the transition becomes much complicated. Compile-time impact looks neutral: https://llvm-compile-time-tracker.com/compare.php?from=32d6b2139a6c8f79e074e8c6cfe0cc9e79c4c0c8&to=e47c26e3f1bf9eb062684dda4fafce58438e994b&stat=instructions:u This patch removes many dead error-handling codes: dtcxzyw/llvm-opt-benchmark#3012 Closes #165179.
…o the domain of conditions (#165748) In simplifycfg/cvp/sccp, we eliminate dead edges of switches according to the knownbits/range info of conditions. However, these approximations may not meet the real-world needs when the domain of condition values is sparse. For example, if the condition can only be either -3 or 3, we cannot prove that the condition never evaluates to 1 (knownbits: ???????1, range: [-3, 4)). This patch adds a helper function `collectPossibleValues` to enumerate all the possible values of V. To fix the motivating issue, `eliminateDeadSwitchCases` will use the result to remove dead edges. Note: In https://discourse.llvm.org/t/missed-optimization-due-to-overflow-check/88700 I proposed a new value lattice kind to represent such values. But I find it hard to apply because the transition becomes much complicated. Compile-time impact looks neutral: https://llvm-compile-time-tracker.com/compare.php?from=32d6b2139a6c8f79e074e8c6cfe0cc9e79c4c0c8&to=e47c26e3f1bf9eb062684dda4fafce58438e994b&stat=instructions:u This patch removes many dead error-handling codes: dtcxzyw/llvm-opt-benchmark#3012 Closes llvm/llvm-project#165179.
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Link: llvm/llvm-project#165748
Requested by: @dtcxzyw