From 11ffb47af0acdf30e29c205add40d34e62bec28f Mon Sep 17 00:00:00 2001
From: Phillip Stephens <antidote.crk@gmail.com>
Date: Tue, 4 Oct 2022 22:17:40 -0700
Subject: [PATCH] Match and link __mem

Former-commit-id: fb1a503ccef3d883f37d6542d08a38acbfde8771
---
 configure.py        |  5 ++-
 libc/string.h       |  2 +-
 src/Runtime/__mem.c | 87 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 92 insertions(+), 2 deletions(-)
 create mode 100644 src/Runtime/__mem.c

diff --git a/configure.py b/configure.py
index 2f577449..cea2eed7 100755
--- a/configure.py
+++ b/configure.py
@@ -13,6 +13,8 @@ parser.add_argument('--map', dest='map', action=argparse.BooleanOptionalAction,
                     default=False, help='generate map file')
 parser.add_argument('--check', dest='check', action=argparse.BooleanOptionalAction,
                     default=True, help='check hash of resulting dol')
+parser.add_argument('--static-libs', dest='static_libs', action=argparse.BooleanOptionalAction,
+                    default=False, help='build and use static libs')
 args = parser.parse_args()
 
 # Completed c/cpp files to link
@@ -66,6 +68,7 @@ COMPLETE_OBJECTS = [
     "Dolphin/os/__start",
     "Dolphin/os/OSAudioSystem",
     "Dolphin/os/__ppc_eabi_init",
+    "Runtime/__mem",
     "Runtime/abort_exit",
     "Runtime/ctype",
     "Runtime/locale",
@@ -1113,7 +1116,7 @@ LIBS = [
 
 # Create & link static libraries
 # Disabled by default for now until we can get it working on windows/macOS
-ENABLE_STATIC_LIBS = False
+ENABLE_STATIC_LIBS = args.static_libs
 
 # On Windows, we need this to use && in commands
 ALLOW_CHAIN = "cmd /c " if os.name == "nt" else ""
diff --git a/libc/string.h b/libc/string.h
index 58966199..59b88938 100644
--- a/libc/string.h
+++ b/libc/string.h
@@ -10,7 +10,7 @@ extern "C" {
 #pragma section code_type ".init"
 void* memcpy(void* dst, const void* src, size_t n);
 void* memset(void* dst, int val, size_t n);
-void __fill_mem(void* dst, int val, unsigned long n);
+void __fill_mem(void* dst, int val, size_t n);
 #pragma section code_type
 
 size_t strlen(const char* s);
diff --git a/src/Runtime/__mem.c b/src/Runtime/__mem.c
new file mode 100644
index 00000000..aa647a78
--- /dev/null
+++ b/src/Runtime/__mem.c
@@ -0,0 +1,87 @@
+#include "string.h"
+
+
+void* memcpy(void* dst, const void* src, size_t n) {
+  const char* p;
+  char* q;
+  int rev = ((unsigned long)src < (unsigned long)dst);
+
+  if (!rev) {
+
+    for (p = (const char*)src - 1, q = (char*)dst - 1, n++; --n;)
+      *++q = *++p;
+
+  } else {
+    for (p = (const char*)src + n, q = (char*)dst + n, n++; --n;)
+      *--q = *--p;
+  }
+  return (dst);
+}
+
+
+#define cps ((unsigned char*)src)
+#define cpd ((unsigned char*)dst)
+#define lps ((unsigned long*)src)
+#define lpd ((unsigned long*)dst)
+#define deref_auto_inc(p) *++(p)
+
+void __fill_mem(void* dst, int val, size_t n) {
+  unsigned long v = (unsigned char)val;
+  unsigned long i;
+
+  cpd = ((unsigned char*)dst) - 1;
+
+  if (n >= 32) {
+    i = (~(unsigned long)dst) & 3;
+
+    if (i) {
+      n -= i;
+
+      do
+        deref_auto_inc(cpd) = v;
+      while (--i);
+    }
+
+    if (v)
+      v |= v << 24 | v << 16 | v << 8;
+
+    lpd = ((unsigned long*)(cpd + 1)) - 1;
+
+    i = n >> 5;
+
+    if (i)
+      do {
+        deref_auto_inc(lpd) = v;
+        deref_auto_inc(lpd) = v;
+        deref_auto_inc(lpd) = v;
+        deref_auto_inc(lpd) = v;
+        deref_auto_inc(lpd) = v;
+        deref_auto_inc(lpd) = v;
+        deref_auto_inc(lpd) = v;
+        deref_auto_inc(lpd) = v;
+      } while (--i);
+
+    i = (n & 31) >> 2;
+
+    if (i)
+      do
+        deref_auto_inc(lpd) = v;
+      while (--i);
+
+    cpd = ((unsigned char*)(lpd + 1)) - 1;
+
+    n &= 3;
+  }
+
+  if (n)
+    do
+      deref_auto_inc(cpd) = v;
+    while (--n);
+
+  return;
+}
+
+void* memset(void* str, int c, size_t n) {
+  __fill_mem(str, c, n);
+  return str;
+}