From f78d6af7319aa676a0f9f6cbb982f21c96e9aac5 Mon Sep 17 00:00:00 2001
From: Michael Liao <michael.hliao@gmail.com>
Date: Thu, 7 Jan 2021 05:24:12 -0500
Subject: [PATCH] [hip] Enable HIP compilation with `<complex`> on MSVC.

- MSVC has different `<complex>` implementation which calls into functions
  declared in `<ymath.h>`. Provide their device-side implementation to enable
  `<complex>` compilation on HIP Windows.

Differential Revision: https://reviews.llvm.org/D93638
---
 clang/lib/Headers/__clang_hip_cmath.h | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/clang/lib/Headers/__clang_hip_cmath.h b/clang/lib/Headers/__clang_hip_cmath.h
index 3a70258..128d64e 100644
--- a/clang/lib/Headers/__clang_hip_cmath.h
+++ b/clang/lib/Headers/__clang_hip_cmath.h
@@ -624,6 +624,34 @@ _GLIBCXX_END_NAMESPACE_VERSION
 } // namespace std
 #endif
 
+// Define device-side math functions from <ymath.h> on MSVC.
+#if defined(_MSC_VER)
+#if defined(__cplusplus)
+extern "C" {
+#endif // defined(__cplusplus)
+__DEVICE__ __attribute__((overloadable)) double _Cosh(double x, double y) {
+  return cosh(x) * y;
+}
+__DEVICE__ __attribute__((overloadable)) float _FCosh(float x, float y) {
+  return coshf(x) * y;
+}
+__DEVICE__ __attribute__((overloadable)) short _Dtest(double *p) {
+  return fpclassify(*p);
+}
+__DEVICE__ __attribute__((overloadable)) short _FDtest(float *p) {
+  return fpclassify(*p);
+}
+__DEVICE__ __attribute__((overloadable)) double _Sinh(double x, double y) {
+  return sinh(x) * y;
+}
+__DEVICE__ __attribute__((overloadable)) float _FSinh(float x, float y) {
+  return sinhf(x) * y;
+}
+#if defined(__cplusplus)
+}
+#endif // defined(__cplusplus)
+#endif // defined(_MSC_VER)
+
 #pragma pop_macro("__DEVICE__")
 
 #endif // __CLANG_HIP_CMATH_H__
-- 
2.7.4