Fix register confusion in non-VFP3 BinaryOpStubs on ARM

Fix register confusion in non-VFP3 BinaryOpStubs on ARM


Committed: https://code.google.com/p/v8/source/detail?r=12980

[Jakob Kummerow, 2012-11-15 17:28:42]

PTAL.

Most of the changes are simple renamings to increase sanity levels; but there
are also no less than four real bug fixes :-)

https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc
File src/arm/code-stubs-arm.cc (right):

https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc#new...
src/arm/code-stubs-arm.cc:870: __ bic(scratch1, dst_exponent,
Operand(HeapNumber::kSignMask));
Bug fix 1: This code cleared the mantissa's sign bit!

https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc#new...
src/arm/code-stubs-arm.cc:878: DoubleIs32BitInteger(masm, dst_exponent,
dst_mantissa, scratch1, scratch2,
Bug fix 2: This call passed in the exponent/mantissa registers in the wrong
order.

https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc#new...
src/arm/code-stubs-arm.cc:883: __ Pop(dst_exponent, dst_mantissa);
Bug fix 3: Restore the "object" register before reloading the double value from
it.

https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc#new...
src/arm/code-stubs-arm.cc:891: __ Pop(dst_exponent, dst_mantissa);
Bug fix 4: Restore original inputs before calling the runtime.

[Yang, 2012-11-16 08:50:08]

On 2012/11/15 17:28:42, Jakob wrote:
> PTAL.
> 
> Most of the changes are simple renamings to increase sanity levels; but there
> are also no less than four real bug fixes :-)
> 
> https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc
> File src/arm/code-stubs-arm.cc (right):
> 
>
https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc#new...
> src/arm/code-stubs-arm.cc:870: __ bic(scratch1, dst_exponent,
> Operand(HeapNumber::kSignMask));
> Bug fix 1: This code cleared the mantissa's sign bit!
> 
>
https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc#new...
> src/arm/code-stubs-arm.cc:878: DoubleIs32BitInteger(masm, dst_exponent,
> dst_mantissa, scratch1, scratch2,
> Bug fix 2: This call passed in the exponent/mantissa registers in the wrong
> order.
> 
>
https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc#new...
> src/arm/code-stubs-arm.cc:883: __ Pop(dst_exponent, dst_mantissa);
> Bug fix 3: Restore the "object" register before reloading the double value
from
> it.
> 
>
https://codereview.chromium.org/11413014/diff/1/src/arm/code-stubs-arm.cc#new...
> src/arm/code-stubs-arm.cc:891: __ Pop(dst_exponent, dst_mantissa);
> Bug fix 4: Restore original inputs before calling the runtime.

LGTM. Nice catch!