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Update docs on dynamic condition code calculation

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Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
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Blue Swirl 2009-05-10 18:23:46 +00:00
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qemu-tech.texi
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@ -363,7 +363,9 @@ look at @code{tcg/README}.
Lazy evaluation of CPU condition codes (@code{EFLAGS} register on x86)
is important for CPUs where every instruction sets the condition
codes. It tends to be less important on conventional RISC systems
where condition codes are only updated when explicitly requested.
where condition codes are only updated when explicitly requested. On
Sparc64, costly update of both 32 and 64 bit condition codes can be
avoided with lazy evaluation.
Instead of computing the condition codes after each x86 instruction,
QEMU just stores one operand (called @code{CC_SRC}), the result
@ -376,8 +378,8 @@ conditional branches.
@code{CC_OP} is almost never explicitly set in the generated code
because it is known at translation time.
The lazy condition code evaluation is used on x86, m68k and cris. ARM
uses a simplified variant for the N and Z flags.
The lazy condition code evaluation is used on x86, m68k, cris and
Sparc. ARM uses a simplified variant for the N and Z flags.
@node CPU state optimisations
@section CPU state optimisations