[llvm] [X86][SSE] Don't emit SSE2 load instructions in SSE1-only mode (PR #134547)

[Simon Pilgrim via llvm-commits]

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@@ -396,9 +397,10 @@ bool X86FixupVectorConstantsPass::processInstruction(MachineFunction &MF,
   case X86::MOVUPDrm:
   case X86::MOVUPSrm:
     // TODO: SSE3 MOVDDUP Handling
-    return FixupConstant({{X86::MOVSSrm, 1, 32, rebuildZeroUpperCst},
-                          {X86::MOVSDrm, 1, 64, rebuildZeroUpperCst}},
-                         128, 1);
+    return FixupConstant(
+        {{X86::MOVSSrm, 1, 32, rebuildZeroUpperCst},
+         {HasSSE2 ? X86::MOVSDrm : 0, 1, 64, rebuildZeroUpperCst}},
+        128, 1);
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RKSimon wrote:

Convert this to the `FixupEntry Fixups[] = {` pattern used below

https://github.com/llvm/llvm-project/pull/134547