[llvm] [SPIRV] Fix code quality issues. (PR #152005)

[Nathan Gauër via llvm-commits]

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@@ -474,6 +474,7 @@ Register SPIRVGlobalRegistry::getOrCreateBaseRegister(
   }
   if (Type->getOpcode() == SPIRV::OpTypeFloat) {
     SPIRVType *SpvBaseType = getOrCreateSPIRVFloatType(BitWidth, I, TII);
+    assert(isa<ConstantFP>(Val) && "Expected ConstantFP for OpTypeFloat");
     return getOrCreateConstFP(dyn_cast<ConstantFP>(Val)->getValue(), I,
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Keenuts wrote:

If we expect Val to be a ConstantFP, don't assert before, but replace the `dyn_cast` by a `cast`. Cast will fail if it's not the correct type.

https://github.com/llvm/llvm-project/pull/152005