From 482704df27ccc79ea96e3ffe93b8c7c19703409a Mon Sep 17 00:00:00 2001
From: Pete Batard <pete@akeo.ie>
Date: Mon, 13 May 2019 09:54:14 +0100
Subject: [PATCH] ArmPkg/CompilerIntrinsicsLib: Add memcmp, memmove intrinsics
 for MSFT

We could have reused memmove.asm for ARM, but we would still need to add
an implemention for ARM64, so we use the same source for both archs.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Pete Batard <pete@akeo.ie>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
---
 .../CompilerIntrinsicsLib.inf                 |  2 ++
 .../Library/CompilerIntrinsicsLib/memcmp_ms.c | 31 +++++++++++++++++
 .../CompilerIntrinsicsLib/memmove_ms.c        | 34 +++++++++++++++++++
 3 files changed, 67 insertions(+)
 create mode 100644 ArmPkg/Library/CompilerIntrinsicsLib/memcmp_ms.c
 create mode 100644 ArmPkg/Library/CompilerIntrinsicsLib/memmove_ms.c

diff --git a/ArmPkg/Library/CompilerIntrinsicsLib/CompilerIntrinsicsLib.inf b/ArmPkg/Library/CompilerIntrinsicsLib/CompilerIntrinsicsLib.inf
index 0203ecb487..d6cc63db75 100644
--- a/ArmPkg/Library/CompilerIntrinsicsLib/CompilerIntrinsicsLib.inf
+++ b/ArmPkg/Library/CompilerIntrinsicsLib/CompilerIntrinsicsLib.inf
@@ -26,6 +26,8 @@
 
   memcpy_ms.c          | MSFT
   memset_ms.c          | MSFT
+  memcmp_ms.c          | MSFT
+  memmove_ms.c         | MSFT
 
 [Sources.ARM]
   Arm/mullu.asm        | RVCT
diff --git a/ArmPkg/Library/CompilerIntrinsicsLib/memcmp_ms.c b/ArmPkg/Library/CompilerIntrinsicsLib/memcmp_ms.c
new file mode 100644
index 0000000000..551f8e77c1
--- /dev/null
+++ b/ArmPkg/Library/CompilerIntrinsicsLib/memcmp_ms.c
@@ -0,0 +1,31 @@
+//------------------------------------------------------------------------------
+//
+// Copyright (c) 2019, Pete Batard. All rights reserved.
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+//------------------------------------------------------------------------------
+
+#if defined(_M_ARM64)
+typedef unsigned __int64  size_t;
+#else
+typedef unsigned __int32  size_t;
+#endif
+
+int memcmp(void *, void *, size_t);
+#pragma intrinsic(memcmp)
+#pragma function(memcmp)
+int memcmp(const void *s1, const void *s2, size_t n)
+{
+  unsigned char const *t1 = s1;
+  unsigned char const *t2 = s2;
+
+  while (n--) {
+    if (*t1 != *t2)
+      return (int)*t1 - (int)*t2;
+    t1++;
+    t2++;
+  }
+
+  return 0;
+}
diff --git a/ArmPkg/Library/CompilerIntrinsicsLib/memmove_ms.c b/ArmPkg/Library/CompilerIntrinsicsLib/memmove_ms.c
new file mode 100644
index 0000000000..5b261ef8b9
--- /dev/null
+++ b/ArmPkg/Library/CompilerIntrinsicsLib/memmove_ms.c
@@ -0,0 +1,34 @@
+//------------------------------------------------------------------------------
+//
+// Copyright (c) 2019, Pete Batard. All rights reserved.
+//
+// SPDX-License-Identifier: BSD-2-Clause-Patent
+//
+//------------------------------------------------------------------------------
+
+#if defined(_M_ARM64)
+typedef unsigned __int64  size_t;
+#else
+typedef unsigned __int32  size_t;
+#endif
+
+void* memmove(void *, const void *, size_t);
+#pragma intrinsic(memmove)
+#pragma function(memmove)
+void* memmove(void *dest, const void *src, size_t n)
+{
+  unsigned char *d = dest;
+  unsigned char const *s = src;
+
+  if (d < s) {
+    while (n--)
+      *d++ = *s++;
+  } else {
+    d += n;
+    s += n;
+    while (n--)
+      *--d = *--s;
+  }
+
+  return dest;
+}