pre-commit: PR173022 #3204
pre-commit: PR173022 #3204
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Diff moderunner: ariselab-64c-docker 2704 files changed, 644161 insertions(+), 651408 deletions(-) +29 box2d/distance.ll |
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Here's a concise summary of the major changes in the patch:
These changes collectively reflect aggressive IR-level optimizations—particularly CFG simplification, dead block elimination, alignment-aware codegen, and precise phi maintenance—across diverse codebases. model: qwen-plus-latest |
| i32 3, label %226 | ||
| i32 1, label %210 | ||
| i32 2, label %213 | ||
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correlated-propagation is sensitive to the difference in PHI incoming value order, causing such regression.
original: LVI infered that %212 ∈ [4,3)
%212 = phi i32 [ 1, %b2SolveSimplex2.exit.thread.thread ], [ 2, %203 ], [ %202, %b2SolveSimplex2.exit ]- init: from pred
%b2SolveSimplex2.exit.thread.thread ],%212 ∈ [1, 2) - merge: from pred
%203,%212 ∈ [1, 3) = [1,2) ∪ [2, 3) - merge: from pred
%b2SolveSimplex2.exit,%212 ∈ [4, 3) = [1, 3) ∪ [4, 1)%b2SolveSimplex2.exitis switch default with arms1, 2, 3, thus we can infer that%202 ∈ [4, 1)
- finally:
%212 ∈ [4, 3), i.e.,%212 != 3
new: : LVI infered that %212 = overdefined
%212 = phi i32 [ 2, %203 ], [ %202, %b2SolveSimplex2.exit ], [ 1, %b2SolveSimplex2.exit.thread.thread ]- init: from pred
%b2SolveSimplex2.exit.thread.thread ],%212 ∈ [2, 3) - merge: from pred
%b2SolveSimplex2.exit,%212 ∈ [2,1) = [2, 3) ∪ [4, 1)%b2SolveSimplex2.exitis switch default with arms1, 2, 3, thus we can infer that%202 ∈ [4, 1)
- merge: from pred
%203,%212 = overdefined = [2,1) ∪ [1,2) - finally:
%212 = overdefined
| switch.edge80.i: ; preds = %30 | ||
| br label %.thread93.i | ||
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| .fold.split77.i: ; preds = %30 | ||
| br label %.thread93.i | ||
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| .fold.split78.i: ; preds = %30 | ||
| br label %.thread93.i | ||
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| .fold.split79.i: ; preds = %30 | ||
| br label %.thread93.i | ||
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| .fold.split81.i: ; preds = %30, %30, %30, %30 | ||
| br label %.thread93.i | ||
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These arms should have been folded into a switch table lookup by `simplifycfg.
| %41 = and i32 %4, 3 | ||
| %42 = xor i32 %41, 3 | ||
| %43 = or i32 %42, %3 |
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These are speculative insns, which could not be sunk by simplifycfg<sink-common-insts>
2 participants
Link: llvm/llvm-project#173022
Requested by: @Camsyn