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abhishek-kaushik22 · abhishek-kaushik22 · commit 345c8fa8a9ce · 2025-02-22T23:35:36.000+05:30
diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
@@ -1357,7 +1357,8 @@ static void computeKnownBitsFromOperator(const Operator *I,
         Known.insertBits(KnownSrc, ShiftElt * SubBitWidth);
       }
     }
-
+    // Look through a cast from wider vector elements to narrow type.
+    // Examples: v2i64 -> v4i32
     if (SubBitWidth % BitWidth == 0) {
       unsigned SubScale = SubBitWidth / BitWidth;
       KnownBits KnownSrc(SubBitWidth);

Original file line number	Diff line number	Diff line change
`@@ -1357,7 +1357,8 @@ static void computeKnownBitsFromOperator(const Operator *I,`
`1357`	`1357`	`Known.insertBits(KnownSrc, ShiftElt * SubBitWidth);`
`1358`	`1358`	`}`
`1359`	`1359`	`}`
`1360`		`-`
	`1360`	`+ // Look through a cast from wider vector elements to narrow type.`
	`1361`	`+ // Examples: v2i64 -> v4i32`
`1361`	`1362`	`if (SubBitWidth % BitWidth == 0) {`
`1362`	`1363`	`unsigned SubScale = SubBitWidth / BitWidth;`
`1363`	`1364`	`KnownBits KnownSrc(SubBitWidth);`