[clang] [clang] Improve diagnostics for vector builtins (PR #125673)

[Chris B via cfe-commits]

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@@ -12411,16 +12411,13 @@ def err_builtin_is_within_lifetime_invalid_arg : Error<
   "%select{non-|function }0pointer argument to '__builtin_is_within_lifetime' "
   "is not allowed">;
 
-def err_builtin_invalid_arg_type: Error <
-  "%ordinal0 argument must be "
-  "%select{a vector, integer or floating point type|a matrix|"
-  "a pointer to a valid matrix element type|"
-  "a signed integer or floating point type|a vector type|"
-  "a floating point type|"
-  "a vector of integers|"
-  "an unsigned integer|"
-  "an 'int'|"
-  "a vector of floating points}1 (was %2)">;
+def err_builtin_invalid_arg_type: Error<
+  "%ordinal0 argument must be a"
+  "%select{| scalar| vector| vector,| vector of| scalar or vector of}1"
+  "%select{| integer| signed integer| unsigned integer| 'int'|"
+  " matrix| pointer to a valid matrix element}2"
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llvm-beanz wrote:

Should `matrix` be here or in the first select?

Logically I would think of the usage for this as: "argument index", "data dimensions (scalar/vector/matrix)", "type".

For HLSL we are planning builtins that will accept "scalar, vector, or matrix of 16 or 32-bit floating point type". Not that you need to handle that case today, but it would be nice if it was something we could build upon.

https://github.com/llvm/llvm-project/pull/125673