[llvm] [RegisterPressure] Remove dead defs correctly (PR #156576)

[Hongyu Chen via llvm-commits]

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@@ -477,17 +477,17 @@ class RegisterOperandsCollector {
       collectOperand(*OperI);
 
     // Remove redundant physreg dead defs.
-    for (const VRegMaskOrUnit &P : RegOpers.Defs)
-      removeRegLanes(RegOpers.DeadDefs, P);
+    for (const VRegMaskOrUnit &P : RegOpers.DeadDefs)
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XChy wrote:

Hmm, is there a specification about the order of definitions in a specific instruction? I am confused by such a fact. Do you have any advice on it? Thanks for any information.

https://github.com/llvm/llvm-project/pull/156576