Revert "Reland "[HLSL] Implement the reflect HLSL function"" (#124046)

Reverts #123853

The introduction of `reflect-error.ll` surfaced a bug with the use of
`report_fatal_error` in `SPIRVInstructionSelector` that was propagated
into the pr. This has caused a build-bot breakage, and the work to solve
the underlying issue is tracked here:
#124045. We can re-apply this
commit when the underlying issue is resolved.

Author: inbelic

clang/include/clang/Basic/BuiltinsSPIRV.td

@@ -19,9 +19,3 @@ def SPIRVLength : Builtin {
   let Attributes = [NoThrow, Const];
   let Prototype = "void(...)";
 }
-
-def SPIRVReflect : Builtin {
-  let Spellings = ["__builtin_spirv_reflect"];
-  let Attributes = [NoThrow, Const];
-  let Prototype = "void(...)";
-}

clang/lib/CodeGen/CGBuiltin.cpp

@@ -20433,19 +20433,6 @@ Value *CodeGenFunction::EmitSPIRVBuiltinExpr(unsigned BuiltinID,
         /*ReturnType=*/X->getType()->getScalarType(), Intrinsic::spv_length,
         ArrayRef<Value *>{X}, nullptr, "spv.length");
   }
-  case SPIRV::BI__builtin_spirv_reflect: {
-    Value *I = EmitScalarExpr(E->getArg(0));
-    Value *N = EmitScalarExpr(E->getArg(1));
-    assert(E->getArg(0)->getType()->hasFloatingRepresentation() &&
-           E->getArg(1)->getType()->hasFloatingRepresentation() &&
-           "Reflect operands must have a float representation");
-    assert(E->getArg(0)->getType()->isVectorType() &&
-           E->getArg(1)->getType()->isVectorType() &&
-           "Reflect operands must be a vector");
-    return Builder.CreateIntrinsic(
-        /*ReturnType=*/I->getType(), Intrinsic::spv_reflect,
-        ArrayRef<Value *>{I, N}, nullptr, "spv.reflect");
-  }
   }
   return nullptr;
 }

clang/lib/Headers/hlsl/hlsl_detail.h

@@ -79,22 +79,6 @@ constexpr enable_if_t<is_same<float, T>::value || is_same<half, T>::value, T>
 distance_vec_impl(vector<T, N> X, vector<T, N> Y) {
   return length_vec_impl(X - Y);
 }
-
-template <typename T>
-constexpr enable_if_t<is_same<float, T>::value || is_same<half, T>::value, T>
-reflect_impl(T I, T N) {
-  return I - 2 * N * I * N;
-}
-
-template <typename T, int L>
-constexpr vector<T, L> reflect_vec_impl(vector<T, L> I, vector<T, L> N) {
-#if (__has_builtin(__builtin_spirv_reflect))
-  return __builtin_spirv_reflect(I, N);
-#else
-  return I - 2 * N * __builtin_hlsl_dot(I, N);
-#endif
-}
-
 } // namespace __detail
 } // namespace hlsl
 #endif //_HLSL_HLSL_DETAILS_H_

clang/lib/Headers/hlsl/hlsl_intrinsics.h

@@ -2008,49 +2008,6 @@ double3 rcp(double3);
 _HLSL_BUILTIN_ALIAS(__builtin_hlsl_elementwise_rcp)
 double4 rcp(double4);
 
-//===----------------------------------------------------------------------===//
-// reflect builtin
-//===----------------------------------------------------------------------===//
-
-/// \fn T reflect(T I, T N)
-/// \brief Returns a reflection using an incident ray, \a I, and a surface
-/// normal, \a N.
-/// \param I The incident ray.
-/// \param N The surface normal.
-///
-/// The return value is a floating-point vector that represents the reflection
-/// of the incident ray, \a I, off a surface with the normal \a N.
-///
-/// This function calculates the reflection vector using the following formula:
-/// V = I - 2 * N * dot(I N) .
-///
-/// N must already be normalized in order to achieve the desired result.
-///
-/// The operands must all be a scalar or vector whose component type is
-/// floating-point.
-///
-/// Result type and the type of all operands must be the same type.
-
-_HLSL_16BIT_AVAILABILITY(shadermodel, 6.2)
-const inline half reflect(half I, half N) {
-  return __detail::reflect_impl(I, N);
-}
-
-const inline float reflect(float I, float N) {
-  return __detail::reflect_impl(I, N);
-}
-
-template <int L>
-_HLSL_16BIT_AVAILABILITY(shadermodel, 6.2)
-const inline vector<half, L> reflect(vector<half, L> I, vector<half, L> N) {
-  return __detail::reflect_vec_impl(I, N);
-}
-
-template <int L>
-const inline vector<float, L> reflect(vector<float, L> I, vector<float, L> N) {
-  return __detail::reflect_vec_impl(I, N);
-}
-
 //===----------------------------------------------------------------------===//
 // rsqrt builtins
 //===----------------------------------------------------------------------===//

clang/lib/Sema/SemaSPIRV.cpp

@@ -69,38 +69,6 @@ bool SemaSPIRV::CheckSPIRVBuiltinFunctionCall(unsigned BuiltinID,
     TheCall->setType(RetTy);
     break;
   }
-  case SPIRV::BI__builtin_spirv_reflect: {
-    if (SemaRef.checkArgCount(TheCall, 2))
-      return true;
-
-    ExprResult A = TheCall->getArg(0);
-    QualType ArgTyA = A.get()->getType();
-    auto *VTyA = ArgTyA->getAs<VectorType>();
-    if (VTyA == nullptr) {
-      SemaRef.Diag(A.get()->getBeginLoc(),
-                   diag::err_typecheck_convert_incompatible)
-          << ArgTyA
-          << SemaRef.Context.getVectorType(ArgTyA, 2, VectorKind::Generic) << 1
-          << 0 << 0;
-      return true;
-    }
-
-    ExprResult B = TheCall->getArg(1);
-    QualType ArgTyB = B.get()->getType();
-    auto *VTyB = ArgTyB->getAs<VectorType>();
-    if (VTyB == nullptr) {
-      SemaRef.Diag(A.get()->getBeginLoc(),
-                   diag::err_typecheck_convert_incompatible)
-          << ArgTyB
-          << SemaRef.Context.getVectorType(ArgTyB, 2, VectorKind::Generic) << 1
-          << 0 << 0;
-      return true;
-    }
-
-    QualType RetTy = ArgTyA;
-    TheCall->setType(RetTy);
-    break;
-  }
   }
   return false;
 }