[clang] [llvm] [HLSL] Implement ddx/ddy_coarse intrinsics (PR #164831)

[Alexander Johnston via llvm-commits]

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@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -verify
+
+typedef float float2 __attribute__((ext_vector_type(2)));
+
+float no_arg() {
+  return __builtin_hlsl_elementwise_ddx_coarse();
+  // expected-error at -1 {{too few arguments to function call, expected 1, have 0}}
+}
+
+float too_many_args(float val) {
+  return __builtin_hlsl_elementwise_ddx_coarse(val, val);
+  // expected-error at -1 {{too many arguments to function call, expected 1, have 2}}
+}
+
+float test_integer_scalar_input(int val) {
+  return __builtin_hlsl_elementwise_ddx_coarse(val);
+  // expected-error at -1 {{1st argument must be a scalar or vector of 16 or 32 bit floating-point types (was 'int')}}
+}
+
+double test_double_scalar_input(double val) {
+  return __builtin_hlsl_elementwise_ddx_coarse(val);
+  // expected-error at -1 {{1st argument must be a scalar or vector of 16 or 32 bit floating-point types (was 'double')}}
+}
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Alexander-Johnston wrote:

Fixed

https://github.com/llvm/llvm-project/pull/164831