Rollup merge of rust-lang#82965 - XAMPPRocky:spv-ext, r=nagisa

Add spirv extension handling in compiletest

We're trying to use `compiletest` for Rust-GPU's testsuite, and ran into an issue with host specific extensions. This adds handling to fix that.

Author: JohnTitor

src/tools/compiletest/src/runtest.rs

@@ -2069,6 +2069,8 @@ impl<'test> TestCx<'test> {
             f = f.with_extra_extension("js");
         } else if self.config.target.contains("wasm32") {
             f = f.with_extra_extension("wasm");
+        } else if self.config.target.contains("spirv") {
+            f = f.with_extra_extension("spv");
         } else if !env::consts::EXE_SUFFIX.is_empty() {
             f = f.with_extra_extension(env::consts::EXE_SUFFIX);
         }