[llvm] [GlobalIsel] Combine zext of trunc (episode II) (PR #108305)

[Matt Arsenault via llvm-commits]

Thorsten =?utf-8?q?Schütt?= <schuett at gmail.com>,
Thorsten =?utf-8?q?Schütt?= <schuett at gmail.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/108305 at github.com>


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@@ -333,8 +333,10 @@ MachineInstrBuilder CSEMIRBuilder::buildConstant(const DstOp &Res,
 
   // For vectors, CSE the element only for now.
   LLT Ty = Res.getLLTTy(*getMRI());
-  if (Ty.isVector())
+  if (Ty.isFixedVector())
     return buildSplatBuildVector(Res, buildConstant(Ty.getElementType(), Val));
+  if (Ty.isScalableVector())
+    return buildSplatVector(Res, buildConstant(Ty.getElementType(), Val));
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arsenm wrote:

Yes, but I don't understand why it would be that way (or why this would be an implementation detail users of the MachineIRBuilder would need to concern themselves with) 

https://github.com/llvm/llvm-project/pull/108305