[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
 
 //
 // ---------- No Native Half support test -----------
 //
 // RUN: %clang_cc1 -finclude-default-header -x hlsl -triple \
-// RUN:   spirv-unknown-vulkan-compute %s -emit-llvm -disable-llvm-passes \
+// RUN:   spirv-unknown-vulkan-compute %s -emit-llvm \
 // RUN:   -o - | FileCheck %s \
 // RUN:   -DFNATTRS="spir_func noundef nofpclass(nan inf)" -DTYPE=float
 
 
 
+// DXCHECK: define [[FNATTRS]] [[TYPE]] @
+// DXCHECK: %div1.i = fdiv reassoc nnan ninf nsz arcp afn [[TYPE]]
----------------
Icohedron wrote:

I would leave the llvm passes disabled because the passes are eliminating some of the instructions you are emitting.
You can use [string substitution substitution blocks](https://llvm.org/docs/CommandGuide/FileCheck.html#filecheck-string-substitution-blocks) to replace register names like %7 with something more descriptive.

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