[llvm] [SPIR-V] Implement SPV_KHR_float_controls2 (PR #146941)

[Dmitry Sidorov via llvm-commits]

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@@ -0,0 +1,95 @@
+; RUN: llc -verify-machineinstrs -O0 -mtriple=spirv64-unknown-unknown --spirv-ext=+SPV_KHR_float_controls2 %s -o - | FileCheck %s
+; TODO: %if spirv-tools %{ llc -O0 -mtriple=spirv64-unknown-unknown --spirv-ext=+SPV_KHR_float_controls2 %s -o - -filetype=obj | spirv-val %}
+
+; CHECK-DAG: Capability FloatControls2 
+; CHECK: Extension "SPV_KHR_float_controls2"
+
+define dso_local dllexport spir_kernel void @k_float_controls_half(half %h) {
+entry:
+  ret void
+}
+
+define dso_local dllexport spir_kernel void @k_float_controls_bfloat(bfloat %b) {
+entry:
+  ret void
+}
+
+define dso_local dllexport spir_kernel void @k_float_controls_float(float %f) {
+entry:
+  ret void
+}
+
+define dso_local dllexport spir_kernel void @k_float_controls_double(double %d) {
+entry:
+  ret void
+}
+
+define dso_local dllexport spir_kernel void @k_float_controls_fp128(fp128 %fp) {
+entry:
+  ret void
+}
+
+define dso_local dllexport spir_kernel void @k_float_controls_all(half %h, bfloat %b, float %f, double %d, fp128 %fp) {
+entry:
+  ret void
+}
+
+!llvm.module.flags = !{!12}
+!llvm.ident = !{!13}
+!spirv.EntryPoint = !{}
+!spirv.ExecutionMode = !{!17, !18, !19, !20, !21, !22, !23, !24, !25, !26}
+
+
+; CHECK: OpEntryPoint Kernel %[[#KERNEL_HALF:]] "k_float_controls_half"
+!0 = !{ptr @k_float_controls_half, !"k_float_controls_half", !6, i32 0, !6, !7, !8, i32 0, i32 0}
+
+; CHECK: OpEntryPoint Kernel %[[#KERNEL_BFLOAT:]] "k_float_controls_bfloat"
+!1 = !{ptr @k_float_controls_bfloat, !"k_float_controls_bfloat", !6, i32 0, !6, !7, !8, i32 0, i32 0}
+
+; CHECK: OpEntryPoint Kernel %[[#KERNEL_FLOAT:]] "k_float_controls_float"
+!2 = !{ptr @k_float_controls_float, !"k_float_controls_float", !6, i32 0, !6, !7, !8, i32 0, i32 0}
+
+; CHECK: OpEntryPoint Kernel %[[#KERNEL_DOUBLE:]] "k_float_controls_double"
+!3 = !{ptr @k_float_controls_double, !"k_float_controls_double", !6, i32 0, !6, !7, !8, i32 0, i32 0}
+
+; CHECK: OpEntryPoint Kernel %[[#KERNEL_FP128:]] "k_float_controls_fp128"
+!4 = !{ptr @k_float_controls_fp128, !"k_float_controls_fp128", !6, i32 0, !6, !7, !8, i32 0, i32 0}
+
+; CHECK: OpEntryPoint Kernel %[[#KERNEL_ALL:]] "k_float_controls_all"
+!5 = !{ptr @k_float_controls_all, !"k_float_controls_all", !6, i32 0, !6, !7, !8, i32 0, i32 0}
+!6 = !{i32 2, i32 2}
+!7 = !{i32 32, i32 36}
+!8 = !{i32 0, i32 0}
+!12 = !{i32 1, !"wchar_size", i32 4}
+!13 = !{!"clang version 8.0.1"}
+!14 = !{i32 1, i32 0}
+
+; CHECK-DAG: OpExecutionMode %[[#KERNEL_HALF]] FPFastMathDefault %[[#HALF_TYPE:]] 1 
+!17 = !{ptr @k_float_controls_half, i32 6028, half poison, i32 1}
+
+; CHECK-DAG: OpExecutionMode %[[#KERNEL_BFLOAT]] FPFastMathDefault %[[#BFLOAT_TYPE:]] 2 
----------------
MrSidims wrote:

>OpTypeFloat 16

With [encoding](https://registry.khronos.org/SPIR-V/specs/unified1/SPIRV.html#FP_Encoding) different from IEEE-754, right? Otherwise it's a bug in lowering (definitely not related to your patch, yet nice to know ahead of time).

https://github.com/llvm/llvm-project/pull/146941