DLL larger than EXE?

[firace]

Does anyone know why, with PB, the simplest DLL (a "Hello World" DLL) is about 8KB, while the smallest EXE is about 3-4 KB?

(It' not important to me at all - I'm just curious!)

[Keya]

because you forgot to turn Debugger off in the DLL?
5.42 x86 PB MessageRequester("Hello world") EXE = 4608 bytes, DLL = 5120 bytes (including AttachProcess/DetachProcess/AttachThread/DetatchThread functions)

[eesau]

DLLs usually have some initialization (and de-initialization) code that executables lack.

[firace]

because you forgot to turn Debugger off in the DLL?
5.42 x86 PB MessageRequester("Hello world") EXE = 4608 bytes, DLL = 5120 bytes (including AttachProcess/DetachProcess/AttachThread/DetatchThread functions)

No, that's not it... I just checked and I do have the debugger turned off.
But I'm using a different version: 5.31 x86. Maybe something was optimized in the meantime.

[firace]

DLLs usually have some initialization (and de-initialization) code that executables lack.

I do have quite a few DLLs that are just 2-3 KB on my system, though...
For instance: C:\Program Files\Common Files\System\ado\msader15.dll

[Keya]

strange, have a look at the .asm output (compile with purebasic.exe /COMMENTED)

[firace]

strange, have a look at the .asm output (compile with purebasic.exe /COMMENTED)

This is the output. To my noob eyes, nothing special stands out...

Code: Select all

; 
; PureBasic 5.31 (Windows - x86) generated code
; 
; (c) 2014 Fantaisie Software
; 
; The header must remain intact for Re-Assembly
; 
; :DLL
; Requester
; FileSystem
; Date
; Object
; SimpleList
; :System
; KERNEL32
; :Import
; 
format MS COFF
; 
; 
extrn _PB_FreeFileSystem@0
extrn _PB_InitRequester@0
extrn _PB_MessageRequester2@12
extrn _GetModuleHandleA@4
extrn _HeapCreate@12
extrn _HeapDestroy@4
extrn _memset
extrn PB_StringBase
extrn _SYS_InitString@0
extrn _SYS_FreeStrings@0
; 
extrn _PB_StringBasePosition
public _PB_Instance
public _PB_ExecutableType
public _PB_OpenGLSubsystem
public _PB_MemoryBase
public PB_Instance
public PB_MemoryBase
public _PB_EndFunctions
public _DLLEntryPoint@12
public _Procedure0

macro pb_public symbol
{
  public  _#symbol
  public symbol
_#symbol:
symbol:
}

macro    pb_align value { rb (value-1) - ($-_PB_DataSection + value-1) mod value }
macro pb_bssalign value { rb (value-1) - ($-_PB_BSSSection  + value-1) mod value }

; 
section '.code' code readable executable align 4096
; 
; 
_DLLEntryPoint@12:
  CMP    dword [esp+8], 1
  JNE   .SkipProcessAttach
  MOV    eax, [esp+4]
  MOV    [_PB_Instance],eax
  CALL   PB_DllInit
.SkipProcessAttach:
  CMP    dword [esp+8], 2
  JNE   .SkipThreadAttach
.SkipThreadAttach:
  CMP    dword [esp+8], 0
  JNE   .SkipProcessDetach
  CALL  _PB_EOP
.SkipProcessDetach:
  CMP    dword [esp+8], 3
  JNE   .SkipThreadDetach
.SkipThreadDetach:
  MOV    eax,1
  RET    12
; 
PB_DllInit:
  PUSH   dword 0
  PUSH   dword 4096
  PUSH   dword 0
  CALL  _HeapCreate@12
  MOV    [PB_MemoryBase],eax
  CALL  _SYS_InitString@0
  CALL  _PB_InitRequester@0
; DisableDebugger
; 
; 
  RET
_PB_EOP_NoValue:
_PB_EOP:
  CALL  _PB_EndFunctions
  CALL  _SYS_FreeStrings@0
  PUSH   dword [PB_MemoryBase]
  CALL  _HeapDestroy@4
  RET
_PB_EndFunctions:
  CALL  _PB_FreeFileSystem@0
  RET
; 
; 
section '.data' data readable writeable
; 
_PB_DataSection:
_PB_OpenGLSubsystem: db 0
pb_public PB_DEBUGGER_LineNumber
  dd     -1
pb_public PB_DEBUGGER_IncludedFiles
  dd     0
pb_public PB_DEBUGGER_FileName
  db     0
pb_public PB_Compiler_Unicode
  dd     0
pb_public PB_Compiler_Thread
  dd     0
pb_public PB_Compiler_Purifier
  dd     0
pb_public PB_Compiler_Debugger
  dd     0
_PB_ExecutableType: dd 0
public _SYS_StaticStringStart
_SYS_StaticStringStart:
_S2: db "This is a PureBasic DLL !",0
_S1: db "Hello",0
pb_public PB_NullString
  db     0
public _SYS_StaticStringEnd
_SYS_StaticStringEnd:
align 4
align 4
align 4
s_s:
  dd     0
  dd     -1
align 4
; 
section '.bss' readable writeable
_PB_BSSSection:
align 4
; 
I_BSSStart:
_PB_MemoryBase:
PB_MemoryBase: rd 1
_PB_Instance:
PB_Instance: rd 1
; 
align 4
PB_DataPointer rd 1
align 4
align 4
align 4
align 4
I_BSSEnd:
section '.code' code readable executable align 4096
; ProcedureDLL MyFunction()
_Procedure0:
  PS0=4
; MessageRequester("Hello", "This is a PureBasic DLL !", 0)
  PUSH   dword 0
  PUSH   dword _S2
  PUSH   dword _S1
  CALL  _PB_MessageRequester2@12
; EndProcedure
  XOR    eax,eax
_EndProcedure1:
  RET
section '.data' data readable writeable
SYS_EndDataSection: