[M3commit] CVS Update: cm3

[Jay Krell]

CVSROOT:	/usr/cvs
Changes by:	jkrell at birch.	10/03/08 13:26:36

Modified files:
	cm3/m3-sys/m3back/src/: M3x86.m3 Stackx86.i3 Stackx86.m3 

Log message:
	"rewrite" extract to not use tables and always be inlined for 64bit
	
	equivalent C code:
	
	UT __stdcall extract(UT x, uint32 offset, uint32 count)
	{
	x >>= offset;
	x &= ~((~(UT)0) << count);
	return x;
	}
	
	extract32
	00000729: 8B4DEC              MOV ECX tv.126[_m]
	0000072C: 8B5DF4              MOV EBX tv.124[_a32]
	0000072F: D3EB                SHR EBX
	00000731: 8BD1                MOV EDX ECX         This is pointless and I'll try to remove.
	00000733: 8B4DE4              MOV ECX tv.128[_n]
	00000736: BEFFFFFFFF          MOV ESI $4294967295 I'll look for smaller form of this. or esi -1?
	0000073B: D3E6                SHL ESI
	0000073D: F7D6                NOT ESI
	0000073F: 23DE                AND EBX ESI
	
	extract64
	000008E4: 8B4DD8              MOV ECX tv.134[_m]
	000008E7: 8B5DE8              MOV EBX tv.131[_a64]
	000008EA: 8B55EC              MOV EDX tv.131[_a64]+4
	000008ED: 0FADD3              SHRD EBX EDX ECX
	000008F0: D3EA                SHR EDX
	000008F2: F6C120              TEST ECX $32
	000008F5: 7400                JE rel8 L.107
	000008F7: 8BDA                MOV EBX EDX
	000008F9: 33D2                XOR EDX EDX
	set_label L.107
	000008FB: 8BF1                MOV ESI ECX          This is pointless and I'll try to remove.
	000008FD: 8B4DD0              MOV ECX tv.136[_n]
	00000900: BFFFFFFFFF          MOV EDI $4294967295  I'll look for smaller form of this. or edi -1?
	00000905: B8FFFFFFFF          MOV EAX $4294967295  I'll look for smaller form of this. (heck, at least mov edi, eax)
	0000090A: 0FA5F8              SHLD EAX EDI ECX
	0000090D: D3E7                SHL EDI
	0000090F: F6C120              TEST ECX $32
	00000912: 7400                JE rel8 L.108
	00000914: 8BC7                MOV EAX EDI
	00000916: 33FF                XOR EDI EDI
	set_label L.108
	00000918: F7D7                NOT EDI
	0000091A: F7D0                NOT EAX
	0000091C: 23DF                AND EBX EDI
	0000091E: 23D0                AND EDX EAX
	
	having n or m and n (or just m? I think so.) be constant leads to better code
	
	some other small cleanup, like avoiding calling find twice,
	I don't see why it was that way