Don't save eax/ecx/edx: Can clobber them in IA-32.

diff --git a/libmalice.asm b/libmalice.asm
index adb9907d47d9f79ab6fc85fe913fb924a3ff89d6..6e05076187e3c7b91185b045ccc6fd3b49b6ec2a 100644 (file)
--- a/libmalice.asm
+++ b/libmalice.asm
@@ -39,21 +39,18 @@ jmp _start_end      ; poor man's exception handling
 
 global lmPrintChar
 lmPrintChar:   ; void lmPrintChar(int chr)
-push eax       ; will be: syscall number
+   ; eax       ; will be: syscall number
 push ebx       ; will be: stdout fd
-push ecx       ; will be: character start address
-push edx       ; will be: character counter
+   ; ecx       ; will be: character start address
+   ; edx       ; will be: character counter
 
 mov  edx, 1    ; print one char
-lea  ecx, [esp+20]     ; address of the char
+lea  ecx, [esp+8]      ; address of the char
 mov  ebx, 1    ; stdout fd
 mov  eax, 4    ; write()
 int 0x80
 
-pop edx
-pop ecx
 pop ebx
-pop eax
 ret
 
 
@@ -64,13 +61,13 @@ ret
 
 global lmPrintString
 lmPrintString: ; void lmPrintString(char *string)
-push eax       ; will be: syscall number
+   ; eax       ; will be: syscall number
 push ebx       ; will be: stdout fd
-push ecx       ; will be: character start address
-push edx       ; will be: character counter
+   ; ecx       ; will be: character start address
+   ; edx       ; will be: character counter
 
 mov  eax, 0            ; prepare for holding a char
-mov  ecx, [esp+20]     ; string start address
+mov  ecx, [esp+8]      ; string start address
 mov  edx, -1           ; init char counter to 0
 
 _print_string_loop:
@@ -83,10 +80,7 @@ mov  ebx, 1  ; stdout fd
 mov  eax, 4    ; write()
 int 0x80
 
-pop edx
-pop ecx
 pop ebx
-pop eax
 ret
 
 
@@ -97,11 +91,11 @@ ret
 
 global lmPrintInt32s
 lmPrintInt32s: ; void lmPrintInt(int num)
-push eax       ; will be: dividend
+   ; eax       ; will be: dividend
 push ebx       ; will be: divisor
-push ecx       ; will be: character start address
-push edx       ; will be: character counter
-mov eax, [esp+20]      ; load num
+   ; ecx       ; will be: character start address
+   ; edx       ; will be: character counter
+mov eax, [esp+8]       ; load num
 sub esp, 12            ; make space for converted integer
 lea ecx, [esp+11]      ; string offset counter, start at lastchar+1
                        ; so writing ends at 10 and char 11 is reserved
@@ -121,7 +115,7 @@ _print_int_loop:
 test eax, eax
 jne _print_int_loop
 
-cmp [esp+32], dword 0  ; check for negative number
+cmp [esp+20], dword 0  ; check for negative number
 jge _print_int_end     ; skip for positive
 dec ecx
 mov [ecx], byte '-'    ; add - sign
@@ -134,10 +128,7 @@ mov  eax, 4        ; write()
 int 0x80       ; let the number speak
 
 add esp, 12
-pop edx
-pop ecx
 pop ebx
-pop eax
 ret
 
 
@@ -149,8 +140,6 @@ ret
 global lmReadChar
 lmReadChar:    ; int lmReadChar(void)
 push ebx
-push ecx
-push edx
 
 sub esp, 4     ; make room for character to be read
 
@@ -172,8 +161,6 @@ mov al, [esp]
 
 _read_char_end:
 add esp, 4
-pop edx
-pop ecx
 pop ebx
 ret
 
@@ -187,8 +174,6 @@ ret
 global lmReadInt32s
 lmReadInt32s:  ; int lmReadInt(void)
 push ebx
-push ecx
-push edx
 push esi       ; negative number info
 push edi       ; actual number
 
@@ -257,8 +242,6 @@ mov eax, edi        ; Return value: The number read
 add esp, 4
 pop edi
 pop esi
-pop edx
-pop ecx
 pop ebx
 ret