Improve Span bounds check elimination by adding _assumeNonNegative to count
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eeckstein
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rjmccall
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Jul 18, 2025
| @@ -626,6 +626,9 @@ void irgen::emitBuiltinCall(IRGenFunction &IGF, const BuiltinInfo &Builtin, | |||
| llvm::MDNode *range = llvm::MDNode::get(ctx, rangeElems); | |||
| I->setMetadata(llvm::LLVMContext::MD_range, range); | |||
| } | |||
| } else { | |||
| auto *cmp = IGF.Builder.CreateICmpSGE(v, llvm::ConstantInt::get(v->getType(), 0)); | |||
| IGF.Builder.CreateIntrinsicCall(llvm::Intrinsic::assume, cmp); | |||
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I'm fine with taking this as is, but we should talk to LLVM about whether they'd prefer we use range metadata or llvm.assume for these going forward, and then make both paths use the one they want.
stephentyrone
approved these changes
Jul 18, 2025
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