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SubjectRe: gcc -O3 and register usage
On Tue, 2003-08-19 at 02:15, J.A. Magallon wrote:

> Does this mean that since PentiumPro gcc has one other register (%dl)
> available, and it uses it only at -O3 ?

AFAIK, the EDX 32-bit register is splitted in two 16-bit halves, being
the least significant half called DX which, at the sime time, is
splitted in two 8-bit halves of which the most significant is called DH,
while the least significant is called DL.

So, DL is not a new register, but the least significant 8-bits from the
EDX CPU register.

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