[llvm] [LAA] Rework getStrideFromPointer, speculate more (PR #212816)

[Ramkumar Ramachandra via llvm-commits]

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@@ -225,8 +226,19 @@ define void @test_versioned_with_different_uses(i32 %offset, ptr noalias %dst.1,
 ; CHECK:       inner.loop.preheader:
 ; CHECK-NEXT:    br label [[VECTOR_SCEVCHECK:%.*]]
 ; CHECK:       vector.scevcheck:
+; CHECK-NEXT:    [[TMP1:%.*]] = icmp slt i32 [[OFFSET]], 0
+; CHECK-NEXT:    [[TMP2:%.*]] = select i1 [[TMP1]], i32 [[TMP0]], i32 [[OFFSET]]
+; CHECK-NEXT:    [[MUL:%.*]] = call { i32, i1 } @llvm.umul.with.overflow.i32(i32 [[TMP2]], i32 200)
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artagnon wrote:

Right, should be fixed by https://github.com/llvm/llvm-project/pull/213662 -- the LAA output is identical, and the issue is stray predicates being added by LVL.

https://github.com/llvm/llvm-project/pull/212816