[llvm] [SPIRV] Return success when selecting reads and writes. (PR #122162)

[Vyacheslav Levytskyy via llvm-commits]

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@@ -3108,12 +3111,16 @@ void SPIRVInstructionSelector::extractSubvector(
   const TargetRegisterClass *ScalarRegClass = GR.getRegClass(ScalarType);
   for (uint64_t I = 0; I < ResultSize; I++) {
     Register ComponentReg = MRI->createVirtualRegister(ScalarRegClass);
-    BuildMI(*InsertionPoint.getParent(), InsertionPoint,
-            InsertionPoint.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
-        .addDef(ComponentReg)
-        .addUse(ScalarType->getOperand(0).getReg())
-        .addUse(ReadReg)
-        .addImm(I);
+    bool Succeed = BuildMI(*InsertionPoint.getParent(), InsertionPoint,
+                           InsertionPoint.getDebugLoc(),
+                           TII.get(SPIRV::OpCompositeExtract))
+                       .addDef(ComponentReg)
+                       .addUse(ScalarType->getOperand(0).getReg())
+                       .addUse(ReadReg)
+                       .addImm(I)
+                       .constrainAllUses(TII, TRI, RBI);
+    if (!Succeed)
+      return false;
     ComponentRegisters.emplace_back(ComponentReg);
   }
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VyacheslavLevytskyy wrote:

We need to add `return true;` here.

https://github.com/llvm/llvm-project/pull/122162