[PATCH] D133567: [AA] Improve the BasicAA analysis capability

[Nikita Popov via Phabricator via llvm-commits]

nikic added inline comments.


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Comment at: llvm/lib/Analysis/BasicAliasAnalysis.cpp:615
+        if (DL.getTypeAllocSize(GTI.getIndexedType()).isScalable() &&
+            (I - GEPOp->op_begin() != GEPOp->getNumOperands() - 1)) {
+          Decomposed.Base = V;
----------------
Please store the getTypeAllocSize() result in a variable and reuse it below. Also, the num operands checks is no longer needed.


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Comment at: llvm/lib/Analysis/BasicAliasAnalysis.cpp:626
 
+      if (isa<ScalableVectorType>(GEPOp->getSourceElementType())) {
+        Decomposed.Base = V;
----------------
Here again we should be checking the alloc size, not the source element type. It should be possible to support something like `getelementptr <vscale x 4 x i32>, ptr %p, i64 0, i64 %i`, where the variable is on a non-scalable index.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D133567/new/

https://reviews.llvm.org/D133567