[X86] Return from SimplifyDemandedBitsForTargetNode for X86ISD::CMOV/ANDP after computing KnownBits. NFC (#141992)

topperc · web-flow · commit 8e2a42aa921f · 2025-05-29T12:59:42.000-07:00
If we break out of the switch, I believe we fall back to the generic
SimplifyDemandedBitsForTargetNode which will call
computeKnownBitsForTargetNode. This will recurse again and calculate
it's own KnownBits. Since we already did the recursion, we should keep
the results.
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -44789,7 +44789,7 @@ bool X86TargetLowering::SimplifyDemandedBitsForTargetNode(
 
     // Only known if known in both the LHS and RHS.
     Known = Known.intersectWith(Known2);
-    break;
+    return false;
   }
   case X86ISD::BEXTR:
   case X86ISD::BEXTRI: {

Original file line number	Diff line number	Diff line change
`@@ -44789,7 +44789,7 @@ bool X86TargetLowering::SimplifyDemandedBitsForTargetNode(`
`44789`	`44789`
`44790`	`44790`	`// Only known if known in both the LHS and RHS.`
`44791`	`44791`	`Known = Known.intersectWith(Known2);`
`44792`		`- break;`
	`44792`	`+ return false;`
`44793`	`44793`	`}`
`44794`	`44794`	`case X86ISD::BEXTR:`
`44795`	`44795`	`case X86ISD::BEXTRI: {`