From 4a3b5393e35d4e7b625d65635c20fe9ef62855bb Mon Sep 17 00:00:00 2001
From: Fei Peng <fei.peng@intel.com>
Date: Tue, 4 Dec 2018 16:06:39 -0800
Subject: [PATCH] Improve BMI2 MultiplyNoFlags APIs (dotnet/coreclr#21362)

Commit migrated from https://github.com/dotnet/coreclr/commit/2217719e39762dc4bb1bb8094b4c4ab86229b004
---
 .../Intrinsics/X86/Bmi2.PlatformNotSupported.cs     | 21 +++++++++++++++++++--
 .../src/System/Runtime/Intrinsics/X86/Bmi2.cs       | 21 +++++++++++++++++++--
 2 files changed, 38 insertions(+), 4 deletions(-)

diff --git a/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Bmi2.PlatformNotSupported.cs b/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Bmi2.PlatformNotSupported.cs
index fd0a2d8..77d3fbf 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Bmi2.PlatformNotSupported.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Bmi2.PlatformNotSupported.cs
@@ -33,9 +33,18 @@ namespace System.Runtime.Intrinsics.X86
             /// <summary>
             /// unsigned __int64 _mulx_u64 (unsigned __int64 a, unsigned __int64 b, unsigned __int64* hi)
             ///   MULX r64a, r64b, reg/m64
+            /// The above native signature does not directly correspond to the managed signature. 
             /// This intrinisc is only available on 64-bit processes
             /// </summary>
-            public static unsafe ulong MultiplyNoFlags(ulong left, ulong right, ulong* high) { throw new PlatformNotSupportedException(); }
+            public static ulong MultiplyNoFlags(ulong left, ulong right) { throw new PlatformNotSupportedException(); }
+
+            /// <summary>
+            /// unsigned __int64 _mulx_u64 (unsigned __int64 a, unsigned __int64 b, unsigned __int64* hi)
+            ///   MULX r64a, r64b, reg/m64
+            /// The above native signature does not directly correspond to the managed signature. 
+            /// This intrinisc is only available on 64-bit processes
+            /// </summary>
+            public static unsafe ulong MultiplyNoFlags(ulong left, ulong right, ulong* low) { throw new PlatformNotSupportedException(); }
 
             /// <summary>
             /// unsigned __int64 _pdep_u64 (unsigned __int64 a, unsigned __int64 mask)
@@ -61,8 +70,16 @@ namespace System.Runtime.Intrinsics.X86
         /// <summary>
         /// unsigned int _mulx_u32 (unsigned int a, unsigned int b, unsigned int* hi)
         ///   MULX r32a, r32b, reg/m32
+        /// The above native signature does not directly correspond to the managed signature. 
+        /// </summary>
+        public static uint MultiplyNoFlags(uint left, uint right) { throw new PlatformNotSupportedException(); }
+
+        /// <summary>
+        /// unsigned int _mulx_u32 (unsigned int a, unsigned int b, unsigned int* hi)
+        ///   MULX r32a, r32b, reg/m32
+        /// The above native signature does not directly correspond to the managed signature. 
         /// </summary>
-        public static unsafe uint MultiplyNoFlags(uint left, uint right, uint* high) { throw new PlatformNotSupportedException(); }
+        public static unsafe uint MultiplyNoFlags(uint left, uint right, uint* low) { throw new PlatformNotSupportedException(); }
 
         /// <summary>
         /// unsigned int _pdep_u32 (unsigned int a, unsigned int mask)
diff --git a/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Bmi2.cs b/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Bmi2.cs
index f535e0a..b701fd0 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Bmi2.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/X86/Bmi2.cs
@@ -33,9 +33,18 @@ namespace System.Runtime.Intrinsics.X86
             /// <summary>
             /// unsigned __int64 _mulx_u64 (unsigned __int64 a, unsigned __int64 b, unsigned __int64* hi)
             ///   MULX r64a, r64b, reg/m64
+            /// The above native signature does not directly correspond to the managed signature. 
             /// This intrinisc is only available on 64-bit processes
             /// </summary>
-            public static unsafe ulong MultiplyNoFlags(ulong left, ulong right, ulong* high) => MultiplyNoFlags(left, right, high);
+            public static ulong MultiplyNoFlags(ulong left, ulong right) => MultiplyNoFlags(left, right);
+
+            /// <summary>
+            /// unsigned __int64 _mulx_u64 (unsigned __int64 a, unsigned __int64 b, unsigned __int64* hi)
+            ///   MULX r64a, r64b, reg/m64
+            /// The above native signature does not directly correspond to the managed signature. 
+            /// This intrinisc is only available on 64-bit processes
+            /// </summary>
+            public static unsafe ulong MultiplyNoFlags(ulong left, ulong right, ulong* low) => MultiplyNoFlags(left, right, low);
 
             /// <summary>
             /// unsigned __int64 _pdep_u64 (unsigned __int64 a, unsigned __int64 mask)
@@ -61,8 +70,16 @@ namespace System.Runtime.Intrinsics.X86
         /// <summary>
         /// unsigned int _mulx_u32 (unsigned int a, unsigned int b, unsigned int* hi)
         ///   MULX r32a, r32b, reg/m32
+        /// The above native signature does not directly correspond to the managed signature. 
+        /// </summary>
+        public static uint MultiplyNoFlags(uint left, uint right) => MultiplyNoFlags(left, right);
+
+        /// <summary>
+        /// unsigned int _mulx_u32 (unsigned int a, unsigned int b, unsigned int* hi)
+        ///   MULX r32a, r32b, reg/m32
+        /// The above native signature does not directly correspond to the managed signature. 
         /// </summary>
-        public static unsafe uint MultiplyNoFlags(uint left, uint right, uint* high) => MultiplyNoFlags(left, right, high);
+        public static unsafe uint MultiplyNoFlags(uint left, uint right, uint* low) => MultiplyNoFlags(left, right, low);
 
         /// <summary>
         /// unsigned int _pdep_u32 (unsigned int a, unsigned int mask)
-- 
2.7.4