[clang] [CIR] X86 vector fcmp-sse vector builtins (PR #167125)

[Andy Kaylor via cfe-commits]

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@@ -43,7 +43,56 @@ mlir::Value CIRGenFunction::emitX86BuiltinExpr(unsigned builtinID,
   // Find out if any arguments are required to be integer constant expressions.
   assert(!cir::MissingFeatures::handleBuiltinICEArguments());
 
-  switch (builtinID) {
+  llvm::SmallVector<mlir::Value, 4> Ops;
+
+  // Find out if any arguments are required to be integer constant expressions.
+  unsigned ICEArguments = 0;
+  ASTContext::GetBuiltinTypeError Error;
+  getContext().GetBuiltinType(BuiltinID, Error, &ICEArguments);
+  assert(Error == ASTContext::GE_None && "Should not codegen an error");
+  for (unsigned i = 0, e = E->getNumArgs(); i != e; i++) {
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andykaylor wrote:

```suggestion
  for (auto [idx, arg] : llvm::enumerate(e->arguments())) {
```
We prefer using range-for loops when possible. Using `llvm::enumerate` tracks the index while still using the range-for. You'll have to change the signature of `emitScalarOrConstFoldImmArg` to take the argument expression (as `const Expr *`) rather than the call expression, but all of the callers of `emitScalarOrConstFoldImmArg` follow the pattern seen here, so that should be fine.

This also avoids the terrible `e` versus `E` ambiguity in the original code here.

https://github.com/llvm/llvm-project/pull/167125