Replying to a message of Sylvain Lauzon to Darryl Gregorash:
DG>> ... after executin [LES BX, THIS],
DG>> ES:BX is a pointer to the first byte of THIS. An equivalen
DG>> 3-instruction sequence is:
SL> not the pointer but the value "THIS" contains. THIS=
SL> 04062354 an LES would have ES=5423 and BX=0604 in the so
SL> scratch register.
Wrong, sorry.. here is what the Intel "Pentium Processor Family Developer's
Manual", vol 3, says (chapter 25, Instruction Set):
LDS/LES/LFS/LGS/LSS Load Full Pointer
Opcode Instruction Clocks Description
(deleted)
Operation
(deleted)
Description
The LGS, LSS, LDS, LES, and LFS instructions read a full pointer from memory
and store it in the selected segment register:register pair. The full pointer
loads 16 bits into the segment register SS, DS, ES, FS, or GS. The other
register loads 32 bits if the operand-size attribute is 32 bits, or loads 16
bits if the operand-size attribute is 16 bits. The other 16- or 32-bit
register to be loaded is determined by the r16 or r32 register operand
specified.
--- FleetStreet 1.21 NR
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* Origin: BIG BANG Burger Bar: Regina SK Canada (1:140/86)
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