Add mechanism to reserve the largest available block of memory below

0x04000000 at the earliest possible moment.  This maximizes the amount
of memory available for Scheme's heap.  Unfortunately, it still isn't
very much space compared to other platforms, and under Visual C++ it
isn't even as much as that provided by Watcom C/C++.  I don't know why
this is so poor, or whether there is anything to be done about it.

diff --git a/v7/src/microcode/memmag.h b/v7/src/microcode/memmag.h
index 830cc94451281b98997cd46dfe0afadc27e1b141..aa6a2762f126b077c3b5e9d6607f8e9bf0164893 100644 (file)
--- a/v7/src/microcode/memmag.h
+++ b/v7/src/microcode/memmag.h
@@ -1,8 +1,8 @@
 /* -*-C-*-
 
-$Id: memmag.h,v 1.5 1996/10/02 18:58:05 cph Exp $
+$Id: memmag.h,v 1.6 1998/04/18 05:39:44 cph Exp $
 
-Copyright (c) 1993-96 Massachusetts Institute of Technology
+Copyright (c) 1993-98 Massachusetts Institute of Technology
 
 This material was developed by the Scheme project at the Massachusetts
 Institute of Technology, Department of Electrical Engineering and
@@ -47,11 +47,13 @@ extern void winnt_deallocate_registers (void);
 #include "ntscmlib.h"
 
 extern BOOL win32_under_win32s_p (void);
+extern char * NT_allocate_heap (unsigned long, unsigned long *);
+extern void NT_release_heap (char *, unsigned long);
 
 #ifdef WINNT_RAW_ADDRESSES
 
-#define WIN32_ALLOCATE_HEAP win32_system_utilities.allocate_heap
-#define WIN32_RELEASE_HEAP win32_system_utilities.release_heap
+#define WIN32_ALLOCATE_HEAP NT_allocate_heap
+#define WIN32_RELEASE_HEAP NT_release_heap
 
 #else /* not WINNT_RAW_ADDRESSES */
 
@@ -86,7 +88,7 @@ WIN32_ALLOCATE_HEAP (unsigned long size, unsigned long * handle)
   total_fudge = (actual_fudge_1 + actual_fudge_2);
   actual_size = (size + total_fudge);
 
-  base = (win32_system_utilities.allocate_heap (actual_size, handle));
+  base = (NT_allocate_heap (actual_size, handle));
   if (base == ((char *) NULL))
     return (base);
 
@@ -112,8 +114,7 @@ WIN32_RELEASE_HEAP (char * area, unsigned long handle)
       (Scheme_Code_Segment_Selector,
        Scheme_Data_Segment_Selector,
        Scheme_Stack_Segment_Selector);  
-  win32_system_utilities.release_heap ((area - total_fudge), handle);
-  return;
+  NT_release_heap ((area - total_fudge), handle);
 }
 
 #endif /* WINNT_RAW_ADDRESSES */

diff --git a/v7/src/microcode/ntgui.c b/v7/src/microcode/ntgui.c
index d1bcba4ffbccd24ce720b5f442a057cf85bc6706..cd88e5fe909a2ddc91aca4c39818908466cf1b6b 100644 (file)
--- a/v7/src/microcode/ntgui.c
+++ b/v7/src/microcode/ntgui.c
@@ -1,6 +1,6 @@
 /* -*-C-*-
 
-$Id: ntgui.c,v 1.22 1998/04/16 06:05:39 cph Exp $
+$Id: ntgui.c,v 1.23 1998/04/18 05:39:22 cph Exp $
 
 Copyright (c) 1993-98 Massachusetts Institute of Technology
 
@@ -44,6 +44,7 @@ MIT in each case. */
 \f
 extern /*static*/ HANDLE  ghInstance = 0;
 extern void scheme_main (int argc, const char ** argv);
+extern void NT_preallocate_heap (void);
 BOOL InitApplication(HANDLE);
 BOOL InitInstance(HANDLE, int);
 
@@ -58,8 +59,8 @@ WinMain (HANDLE hInst, HANDLE hPrevInst, LPSTR lpCmdLine, int nCmdShow)
     char **argv;
     extern int main (int, char **);
 
+    NT_preallocate_heap ();
     ghInstance = hInst;
-
     {
       int cmdlen = strlen(lpCmdLine);
       int maxargs = cmdlen/2+2;

diff --git a/v7/src/microcode/nttop.c b/v7/src/microcode/nttop.c
index 27482042996d8b1cf5e77c408e7407811dcdd167..75ed5496aa91b39c4c6ec26a65ecb2584f28dfee 100644 (file)
--- a/v7/src/microcode/nttop.c
+++ b/v7/src/microcode/nttop.c
@@ -1,8 +1,8 @@
 /* -*-C-*-
 
-$Id: nttop.c,v 1.24 1997/10/26 08:04:18 cph Exp $
+$Id: nttop.c,v 1.25 1998/04/18 05:39:09 cph Exp $
 
-Copyright (c) 1993-97 Massachusetts Institute of Technology
+Copyright (c) 1993-98 Massachusetts Institute of Technology
 
 This material was developed by the Scheme project at the Massachusetts
 Institute of Technology, Department of Electrical Engineering and
@@ -207,6 +207,95 @@ OS_quit (int code, int abnormal_p)
   return;
 }
 \f
+/* Memory Allocation */
+
+static LPVOID NT_heap_base;
+static DWORD NT_heap_size;
+static DWORD NT_heap_error;
+#define SCHEME_ADDR_LIMIT 0x04000000
+
+void
+NT_preallocate_heap (void)
+{
+  MEMORY_BASIC_INFORMATION largest;
+  DWORD scan = 0;
+  (largest.RegionSize) = 0;
+  while (scan < SCHEME_ADDR_LIMIT)
+    {
+      MEMORY_BASIC_INFORMATION info;
+      (void) VirtualQuery (((LPCVOID) scan), (&info), (sizeof (info)));
+      if ((info.State) == MEM_FREE)
+       {
+         DWORD end = (scan + (info.RegionSize));
+         if (end > SCHEME_ADDR_LIMIT)
+           (info.RegionSize) -= (end - SCHEME_ADDR_LIMIT);
+         if ((info.RegionSize) > (largest.RegionSize))
+           largest = info;
+       }
+      scan += (info.RegionSize);
+    }
+  NT_heap_size = (largest.RegionSize);
+  NT_heap_base
+    = (VirtualAlloc ((largest.BaseAddress),
+                    NT_heap_size,
+                    MEM_RESERVE,
+                    PAGE_READWRITE));
+  if (NT_heap_base == 0)
+    NT_heap_error = (GetLastError ());
+}
+
+char *
+NT_allocate_heap (unsigned long size, unsigned long * handle)
+{
+  if (NT_heap_base == 0)
+    {
+      SYSTEM_INFO info;
+      LPVOID start = 0;
+      LPVOID base;
+      GetSystemInfo (&info);
+      while (1)
+       {
+         start = (((char *) start) + (info . dwPageSize));
+         base
+           = (VirtualAlloc (start,
+                            size,
+                            (MEM_RESERVE | MEM_COMMIT),
+                            PAGE_READWRITE));
+         if (base != 0)
+           break;
+       }
+      (* handle) = size;
+      return ((char *) base);
+    }
+  else
+    {
+      DWORD size2 = ((size <= NT_heap_size) ? size : NT_heap_size);
+      LPVOID base
+       = (VirtualAlloc (NT_heap_base,
+                        size2,
+                        MEM_COMMIT,
+                        PAGE_READWRITE));
+      (* handle) = size2;
+      return ((char *) base);
+    }
+}
+
+void
+NT_release_heap (char * area, unsigned long handle)
+{
+  VirtualFree (((LPVOID) area),
+              ((DWORD) handle),
+              ((DWORD) MEM_DECOMMIT));
+  if (NT_heap_base == 0)
+    VirtualFree (((LPVOID) area),
+                ((DWORD) 0),
+                ((DWORD) MEM_RELEASE));
+  else
+    VirtualFree (NT_heap_base,
+                ((DWORD) 0),
+                ((DWORD) MEM_RELEASE));
+}
+\f
 #ifndef EAGAIN
 #define EAGAIN ERRNO_NONBLOCK
 #endif