[clang] [WebAssembly] Change F16x8 extract lane to require constant integer. (PR #108116)

[Derek Schuff via cfe-commits]

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@@ -1888,18 +1888,15 @@ static __inline__ v128_t __FP16_FN_ATTRS wasm_f16x8_splat(float __a) {
   return (v128_t)__builtin_wasm_splat_f16x8(__a);
 }
 
-static __inline__ float __FP16_FN_ATTRS wasm_f16x8_extract_lane(v128_t __a,
-                                                                int __i)
-    __REQUIRE_CONSTANT(__i) {
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dschuff wrote:

out of curiosity, what does this REQUIRE_CONSTANT actually do? 

https://github.com/llvm/llvm-project/pull/108116