[clang] Implement the `fmod` intrinsic (PR #130320)

[Deric C. via cfe-commits]

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@@ -22,56 +22,144 @@
 //
 // RUN: %clang_cc1 -finclude-default-header -x hlsl -triple \
 // RUN:   spirv-unknown-vulkan-compute %s -fnative-half-type \
-// RUN:   -emit-llvm -disable-llvm-passes -o - | FileCheck %s \
+// RUN:   -emit-llvm -o - | FileCheck %s \
 // RUN:   -DFNATTRS="spir_func noundef nofpclass(nan inf)" -DTYPE=half
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Icohedron wrote:

I would add `--check-prefixes=CHECK,SPVCHECK` to signify that `SPVCHECK` is for the SPIR-V codegen only, while `CHECK` is for both DirectX and SPIR-V.

Likewise, for the RUN lines to test the DirectX codegen, change `--check-prefixes=DXCHECK,DXNATIVE_HALF` to `--check-prefixes=CHECK,DXCHECK,DX...`  so that you can use `CHECK` to check for lines that are common between DirectX and SPIR-V codegen


https://github.com/llvm/llvm-project/pull/130320