[llvm] [AArch64][GlobalISel] Lower G_BUILD_VECTOR to G_INSERT_VECTOR_ELT (PR #105686)

[David Green via llvm-commits]

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@@ -1054,6 +1054,40 @@ void applyLowerVectorFCMP(MachineInstr &MI, MachineRegisterInfo &MRI,
   MI.eraseFromParent();
 }
 
+// Matches G_BUILD_VECTOR where at least one source operand is not a constant
+bool matchLowerBuildToInsertVecElt(MachineInstr &MI, MachineRegisterInfo &MRI) {
+  auto *GBuildVec = dyn_cast<GBuildVector>(&MI);
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davemgreen wrote:

dyn_cast -> cast

https://github.com/llvm/llvm-project/pull/105686