[llvm] WebAssembly: Don't duplicate implicit CALL operands in LowerCallResults (PR #225069)

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<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-webassembly

Author: Matt Arsenault (arsenm)

<details>
<summary>Changes</summary>

When recombining the CALL_PARAMS/CALL_RESULTS pseudo-pair into a real CALL,
LowerCallResults copied CallParams.uses() onto the new instruction. uses()
includes the implicit operands (implicit-def $arguments and the implicit
$sp32/$sp64 uses), which the freshly created CALL already carries. This
resulted in a duplicated implicit-def of $arguments. This avoids a future
verifier error.

Co-authored-by: Claude (Claude-Opus-4.8) <noreply@<!-- -->anthropic.com>

---
Full diff: https://github.com/llvm/llvm-project/pull/225069.diff


1 Files Affected:

- (modified) llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp (+2-1) 


``````````diff
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
index ba702afbe3262..1ecd232782679 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.cpp
@@ -867,7 +867,8 @@ LowerCallResults(MachineInstr &CallResults, DebugLoc DL, MachineBasicBlock *BB,
     }
   }
 
-  for (auto Use : CallParams.uses())
+  // Avoid duplicating the implicit operands.
+  for (auto Use : CallParams.explicit_uses())
     MIB.add(Use);
 
   BB->insert(CallResults.getIterator(), MIB);

``````````

</details>


https://github.com/llvm/llvm-project/pull/225069