Index: SOURCE/WIN32/FASM.ASM
==================================================================
--- SOURCE/WIN32/FASM.ASM
+++ SOURCE/WIN32/FASM.ASM
@@ -1,11 +1,11 @@

 ; flat assembler interface for Win32
 ; Copyright (c) 1999-2015, Tomasz Grysztar.
 ; All rights reserved.

-	format	PE console
+	format	PE console large

 section '.text' code readable executable

 start:

@@ -380,11 +380,11 @@
     GetStdHandle dd rva _GetStdHandle
     VirtualAlloc dd rva _VirtualAlloc
     VirtualFree dd rva _VirtualFree
     GetTickCount dd rva _GetTickCount
     GetSystemTime dd rva _GetSystemTime
-    GlobalMemoryStatus dd rva _GlobalMemoryStatus
+    SetUnhandledExceptionFilter dd rva _SetUnhandledExceptionFilter
     dd 0

   kernel_name db 'KERNEL32.DLL',0

   _ExitProcess dw 0
@@ -411,9 +411,9 @@
     db 'VirtualFree',0
   _GetTickCount dw 0
     db 'GetTickCount',0
   _GetSystemTime dw 0
     db 'GetSystemTime',0
-  _GlobalMemoryStatus dw 0
-    db 'GlobalMemoryStatus',0
+  _SetUnhandledExceptionFilter dw 0
+    db 'SetUnhandledExceptionFilter',0

 section '.reloc' fixups data readable discardable

Index: SOURCE/WIN32/SYSTEM.INC
==================================================================
--- SOURCE/WIN32/SYSTEM.INC
+++ SOURCE/WIN32/SYSTEM.INC
@@ -1,5 +1,7 @@
+MEMORY_ALLOCATION_BLOCK_SIZE	= 1 shl 16	;64kB. Higher numbers reduce the number of calls to the allocator. A value of 1 will allocate just the page where the memory is accessed
+MEMORY_ALLOCATION_MAX_SIZE	= 0x7ffc0000	;Windows fails all calls that try to allocate more than this

 ; flat assembler interface for Win32
 ; Copyright (c) 1999-2015, Tomasz Grysztar.
 ; All rights reserved.

@@ -46,52 +48,58 @@
 	mov	[memory_start],eax
 	mov	eax,esp
 	and	eax,not 0FFFh
 	add	eax,1000h-10000h
 	mov	[stack_limit],eax
-	mov	eax,[memory_setting]
-	shl	eax,10
+	mov	ebx,[memory_setting]
+	shl	ebx,10
 	jnz	allocate_memory
-	push	buffer
-	call	[GlobalMemoryStatus]
-	mov	eax,dword [buffer+20]
-	mov	edx,dword [buffer+12]
-	cmp	eax,0
-	jl	large_memory
-	cmp	edx,0
-	jl	large_memory
-	shr	eax,2
-	add	eax,edx
-	jmp	allocate_memory
-    large_memory:
-	mov	eax,80000000h
+	mov	ebx,MEMORY_ALLOCATION_MAX_SIZE
     allocate_memory:
-	mov	edx,eax
-	shr	edx,2
-	mov	ecx,eax
-	sub	ecx,edx
-	mov	[memory_end],ecx
-	mov	[additional_memory_end],edx
 	push	PAGE_READWRITE
-	push	MEM_COMMIT
-	push	eax
+	push	MEM_RESERVE
+	push	ebx
 	push	0
-	call	[VirtualAlloc]
-	or	eax,eax
+	call	[VirtualAlloc]		;allocate the main section
+	test	eax,eax
 	jz	not_enough_memory
 	mov	[memory_start],eax
-	add	eax,[memory_end]
+	add	eax,ebx
+	mov	[memory_end],eax
+	cmp	[memory_setting],0
+	jnz	.use_single_section
+	mov	eax,ebx
+	shr	eax,1
+	push	PAGE_READWRITE
+	push	MEM_RESERVE
+	push	eax
+	push	0
+	call	[VirtualAlloc]		;allocate the additional section
+	test	eax,eax
+	jz	.use_single_section
+	mov	[additional_memory],eax
+	shr	ebx,1
+	add	eax,ebx
+	mov	[additional_memory_end],eax
+    .memory_okay:
+	push	memory_allocation_handler
+	call	[SetUnhandledExceptionFilter]
+	ret
+    .use_single_section:
+	mov	eax,[memory_end]
+	mov	[additional_memory_end],eax
+	shr	ebx,2
+	sub	eax,ebx
 	mov	[memory_end],eax
 	mov	[additional_memory],eax
-	add	[additional_memory_end],eax
-	ret
+	jmp	.memory_okay
     not_enough_memory:
-	mov	eax,[additional_memory_end]
-	shl	eax,1
-	cmp	eax,4000h
-	jb	out_of_memory
-	jmp	allocate_memory
+	shr	ebx,2
+	lea	ebx,[ebx*3]
+	cmp	ebx,4000h
+	jae	allocate_memory
+	jmp	out_of_memory

 exit_program:
 	movzx	eax,al
 	push	eax
 	mov	eax,[memory_start]
@@ -99,12 +107,53 @@
 	jz	do_exit
 	push	MEM_RELEASE
 	push	0
 	push	eax
 	call	[VirtualFree]
+	push	MEM_RELEASE
+	push	0
+	push	[additional_memory]
+	call	[VirtualFree]
     do_exit:
 	call	[ExitProcess]
+
+memory_allocation_handler:
+	mov	eax,[esp+4]	;get pointer to exception information
+	mov	ecx,[eax]	;EXCEPTION_POINTERS.ExceptionRecord
+	mov	edx,[ecx]	;EXCEPTION_RECORD.ExceptionCode
+	cmp	edx,0xc0000005	;EXCEPTION_ACCESS_VIOLATION
+	jnz	.fail
+	mov	edx,[ecx+24]	;EXCEPTION_RECORD.ExceptionAddress
+	cmp	edx,[memory_start]
+	jb	.check_additional
+	mov	eax,[memory_end]
+	sub	eax,edx		;don't allocate more than EAX bytes
+	ja	.allocate
+    .check_additional:
+	cmp	edx,[additional_memory]
+	jb	.fail
+	mov	eax,[additional_memory_end]
+	sub	eax,edx		;don't allocate more than EAX bytes
+	jbe	.fail
+    .allocate:
+	mov	ecx,MEMORY_ALLOCATION_BLOCK_SIZE
+	cmp	eax,ecx
+	jbe	.allocation_size_defined
+	mov	eax,ecx		;don't allocate more than ECX bytes
+    .allocation_size_defined:
+	push	PAGE_READWRITE
+	push	MEM_COMMIT
+	push	eax		;allocate this many bytes
+	push	edx		;at this address
+	call	[VirtualAlloc]
+	test	eax,eax
+	jz	out_of_memory
+	mov	eax,-1		;EXCEPTION_CONTINUE_EXECUTION
+	retn	4
+    .fail:			;some other exception happened
+	mov	eax,0		;EXCEPTION_CONTINUE_SEARCH
+	retn	4

 get_environment_variable:
 	mov	ecx,[memory_end]
 	sub	ecx,edi
 	cmp	ecx,4000h
@@ -162,13 +211,22 @@
 	jz	file_error
 	clc
 	ret
 read:
 	mov	ebp,ecx
+	push	edx
+	push	PAGE_READWRITE
+	push	MEM_COMMIT
+	push	ecx		;allocate the required number of bytes
+	push	edx		;at this address
+	call	[VirtualAlloc]
+	pop	edx
+	test	eax,eax
+	jz	out_of_memory
 	push	0
 	push	bytes_count
-	push	ecx
+	push	ebp
 	push	edx
 	push	ebx
 	call	[ReadFile]
 	or	eax,eax
 	jz	file_error