commit 0c8cda4c7e3dbb6b8529c2920d8ca6ab8201b0b1
author James Price <jrprice@google.com> Fri Jul 21 13:21:00 2023 +0000
committer James Price <jrprice@google.com> Fri Jul 21 13:21:00 2023 +0000
tree 0196a807dfd51c79b73971b20d09c0032f4e2559
parent dbdd49ba13a2dc535b8095f94776b46e5e4b7f2c

[ir][spirv-writer] Handle faceForward builtin

Bug: tint:1906
Change-Id: Idb07f25a49897a8b6ba0d3a9e3c09485cd677af4
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/142366
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>

src/tint/lang/spirv/writer/builtin_test.cc

diff --git a/src/tint/lang/spirv/writer/builtin_test.cc b/src/tint/lang/spirv/writer/builtin_test.cc
index 46f1b73..a398cf8 100644
--- a/src/tint/lang/spirv/writer/builtin_test.cc
+++ b/src/tint/lang/spirv/writer/builtin_test.cc
@@ -1000,6 +1000,38 @@
     EXPECT_INST("%result = OpBitFieldInsert %v2uint %arg %newbits %offset %count");
 }
 
+TEST_F(SpirvWriterTest, Builtin_FaceForward_F32) {
+    auto* arg1 = b.FunctionParam("arg1", ty.vec3<f32>());
+    auto* arg2 = b.FunctionParam("arg2", ty.vec3<f32>());
+    auto* arg3 = b.FunctionParam("arg3", ty.vec3<f32>());
+    auto* func = b.Function("foo", ty.vec3<f32>());
+    func->SetParams({arg1, arg2, arg3});
+    b.With(func->Block(), [&] {
+        auto* result = b.Call(ty.vec3<f32>(), builtin::Function::kFaceForward, arg1, arg2, arg3);
+        b.Return(func, result);
+        mod.SetName(result, "result");
+    });
+
+    ASSERT_TRUE(Generate()) << Error() << output_;
+    EXPECT_INST("%result = OpExtInst %v3float %10 FaceForward %arg1 %arg2 %arg3");
+}
+
+TEST_F(SpirvWriterTest, Builtin_FaceForward_F16) {
+    auto* arg1 = b.FunctionParam("arg1", ty.vec4<f16>());
+    auto* arg2 = b.FunctionParam("arg2", ty.vec4<f16>());
+    auto* arg3 = b.FunctionParam("arg3", ty.vec4<f16>());
+    auto* func = b.Function("foo", ty.vec4<f16>());
+    func->SetParams({arg1, arg2, arg3});
+    b.With(func->Block(), [&] {
+        auto* result = b.Call(ty.vec4<f16>(), builtin::Function::kFaceForward, arg1, arg2, arg3);
+        b.Return(func, result);
+        mod.SetName(result, "result");
+    });
+
+    ASSERT_TRUE(Generate()) << Error() << output_;
+    EXPECT_INST("%result = OpExtInst %v4half %10 FaceForward %arg1 %arg2 %arg3");
+}
+
 TEST_F(SpirvWriterTest, Builtin_Mix_VectorOperands_ScalarFactor) {
     auto* arg1 = b.FunctionParam("arg1", ty.vec4<f32>());
     auto* arg2 = b.FunctionParam("arg2", ty.vec4<f32>());

src/tint/lang/spirv/writer/writer.cc

diff --git a/src/tint/lang/spirv/writer/writer.cc b/src/tint/lang/spirv/writer/writer.cc
index b8db01b..90c338c 100644
--- a/src/tint/lang/spirv/writer/writer.cc
+++ b/src/tint/lang/spirv/writer/writer.cc
@@ -1238,6 +1238,9 @@
             op = result_ty->is_signed_integer_scalar_or_vector() ? spv::Op::OpBitFieldSExtract
                                                                  : spv::Op::OpBitFieldUExtract;
             break;
+        case builtin::Function::kFaceForward:
+            glsl_ext_inst(GLSLstd450FaceForward);
+            break;
         case builtin::Function::kFloor:
             glsl_ext_inst(GLSLstd450Floor);
             break;