[llvm] [ValueTracking] Handle assume( trunc x to i1) (PR #118406)

[Yingwei Zheng via llvm-commits]

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@@ -612,11 +612,16 @@ static bool isKnownNonZeroFromAssume(const Value *V, const SimplifyQuery &Q) {
     // Warning: This loop can end up being somewhat performance sensitive.
     // We're running this loop for once for each value queried resulting in a
     // runtime of ~O(#assumes * #values).
+    Value *Arg = I->getArgOperand(0);
+    if (match(Arg, m_TruncOrSelf(m_Specific(V))) &&
+        isValidAssumeForContext(I, Q.CxtI, Q.DT)) {
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dtcxzyw wrote:

Yeah. The test diff shows it only removes some (unused?) assumptions.


https://github.com/llvm/llvm-project/pull/118406