[HLSL] add ceil library function

[bob80905]

Summary

This change exposes the ceil library function for HLSL,
excluding long, int, and long long doubles.
Ceil is supported for all scalar, vector, and matrix types.

Long and long long double support is missing in this patch because those types
don't exist in HLSL. Int is missing because the ceil function only works on floating type arguments.

The full documentation of the HLSL ceil function is available here:
https://docs.microsoft.com/en-us/windows/win32/direct3dhlsl/dx-graphics-hlsl-ceil

[beanz]

For this builtin you should be able to use __builtin_elementwise_ceil for all the overload cases, and you should be able to add the vector cases too.

[bob80905]

• add elementwise function tests. Remove integer tests, ceil will not take integer types as an arg

[bob80905]

• remove int attribute links in hlsl_intrinsics.h

[python3kgae]

clang/lib/Headers/hlsl/hlsl_intrinsics.h

17–18

The change to remove these already in.
Rebase to skip it in this PR.

[bob80905]

• add elementwise function tests
• remove int attribute links in hlsl_intrinsics.h
• rebase

[bob80905]

fix attempt 1

[bob80905]

fix attempt 2

[bob80905]

• adhere to clang format

[bob80905]

• whitespace try 2

[bob80905]

• got clang-format working on VS2022

clang/lib/Headers/hlsl/hlsl_intrinsics.h

 //===----- hlsl_intrinsics.h - HLSL definitions for intrinsics ----------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef _HLSL_HLSL_INTRINSICS_H_
 #define _HLSL_HLSL_INTRINSICS_H_
 
 __attribute__((availability(shadermodel, introduced = 6.0)))
 __attribute__((clang_builtin_alias(__builtin_hlsl_wave_active_count_bits))) uint
 WaveActiveCountBits(bool bBit);
 
 
 // abs builtins
 #ifdef __HLSL_ENABLE_16_BIT
 __attribute__((clang_builtin_alias(__builtin_elementwise_abs)))
 int16_t abs(int16_t);
 __attribute__((clang_builtin_alias(__builtin_elementwise_abs)))
 int16_t2 abs(int16_t2);
 __attribute__((clang_builtin_alias(__builtin_elementwise_abs)))
 int16_t3 abs(int16_t3);
 __attribute__((clang_builtin_alias(__builtin_elementwise_abs)))
 int16_t4 abs(int16_t4);

 // sqrt builtins
 __attribute__((clang_builtin_alias(__builtin_sqrt))) double sqrt(double In);
 __attribute__((clang_builtin_alias(__builtin_sqrtf))) float sqrt(float In);
 
 #ifdef __HLSL_ENABLE_16_BIT
 __attribute__((clang_builtin_alias(__builtin_sqrtf16))) half sqrt(half In);
 #endif
 
+// ceil builtins
+#ifdef __HLSL_ENABLE_16_BIT
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil))) half ceil(half);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+half2 ceil(half2);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+half3 ceil(half3);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+half4 ceil(half4);
+#endif
+
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil))) float
+ceil(float);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+float2 ceil(float2);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+float3 ceil(float3);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+float4 ceil(float4);
+
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil))) double
+ceil(double);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+double2 ceil(double2);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+double3 ceil(double3);
+__attribute__((clang_builtin_alias(__builtin_elementwise_ceil)))
+double4 ceil(double4);
 
 #endif //_HLSL_HLSL_INTRINSICS_H_

clang/test/CodeGenHLSL/builtins/ceil.hlsl

+// RUN: %clang_cc1 -std=hlsl2021 -finclude-default-header -x hlsl -triple \
+// RUN:   dxil-pc-shadermodel6.3-library %s -fnative-half-type \
+// RUN:   -emit-llvm -disable-llvm-passes -O3 -o - | FileCheck %s
+// RUN: %clang_cc1 -std=hlsl2021 -finclude-default-header -x hlsl -triple \
+// RUN:   dxil-pc-shadermodel6.3-library %s -emit-llvm -disable-llvm-passes \
+// RUN:   -D__HLSL_ENABLE_16_BIT -o - | FileCheck %s --check-prefix=NO_HALF
+
+
+// CHECK: define noundef half @
+// CHECK: call half @llvm.ceil.f16(
+// NO_HALF: define noundef float @"?test_ceil_half@@YA$halff@$halff@@Z"(
+// NO_HALF: call float @llvm.ceil.f32(float %0)
+half test_ceil_half ( half p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <2 x half> @
+// CHECK: call <2 x half> @llvm.ceil.v2f16(
+// NO_HALF: define noundef <2 x float> @"?test_ceil_half2@@YAT?$__vector@$halff@$01@__clang@@T12@@Z"(
+// NO_HALF: call <2 x float> @llvm.ceil.v2f32(
+half2 test_ceil_half2 ( half2 p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <3 x half> @
+// CHECK: call <3 x half> @llvm.ceil.v3f16(
+// NO_HALF: define noundef <3 x float> @"?test_ceil_half3@@YAT?$__vector@$halff@$02@__clang@@T12@@Z"(
+// NO_HALF: call <3 x float> @llvm.ceil.v3f32(
+half3 test_ceil_half3 ( half3 p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <4 x half> @
+// CHECK: call <4 x half> @llvm.ceil.v4f16(
+// NO_HALF: define noundef <4 x float> @"?test_ceil_half4@@YAT?$__vector@$halff@$03@__clang@@T12@@Z"(
+// NO_HALF: call <4 x float> @llvm.ceil.v4f32(
+half4 test_ceil_half4 ( half4 p0 ) {
+  return ceil ( p0 );
+}
+
+// CHECK: define noundef float @
+// CHECK: call float @llvm.ceil.f32(
+float test_ceil_float ( float p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <2 x float> @
+// CHECK: call <2 x float> @llvm.ceil.v2f32(
+float2 test_ceil_float2 ( float2 p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <3 x float> @
+// CHECK: call <3 x float> @llvm.ceil.v3f32(
+float3 test_ceil_float3 ( float3 p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <4 x float> @
+// CHECK: call <4 x float> @llvm.ceil.v4f32(
+float4 test_ceil_float4 ( float4 p0 ) {
+  return ceil ( p0 );
+}
+
+// CHECK: define noundef double @
+// CHECK: call double @llvm.ceil.f64(
+double test_ceil_double ( double p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <2 x double> @
+// CHECK: call <2 x double> @llvm.ceil.v2f64(
+double2 test_ceil_double2 ( double2 p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <3 x double> @
+// CHECK: call <3 x double> @llvm.ceil.v3f64(
+double3 test_ceil_double3 ( double3 p0 ) {
+  return ceil ( p0 );
+}
+// CHECK: define noundef <4 x double> @
+// CHECK: call <4 x double> @llvm.ceil.v4f64(
+double4 test_ceil_double4 ( double4 p0 ) {
+  return ceil ( p0 );
+}