For your information, just a comment about cmp vs tst on ARM.

Alexandre


http://codereview.chromium.org/7489045/diff/27001/src/ia32/lithium-codegen-ia32.cc
File src/ia32/lithium-codegen-ia32.cc (right):

http://codereview.chromium.org/7489045/diff/27001/src/ia32/lithium-codegen-ia32.cc#newcode1559
src/ia32/lithium-codegen-ia32.cc:1559: __ cmp(ToOperand(left),
ToImmediate(right));
I forgot to change it to tst for Intel.
I intentionally used a cmp as it is better on ARM:
- the immediate is encoded in the instruction.
- cmp sets all the flags, whereas tst doesn't, resulting in more complex
handling for the pipeline.

On 2011/10/20 10:28:40, William Hesse wrote:
If the immediate value is 0, this can also be test(left, left) on ia32
and x64.
You should try this on ARM, if possible.  I'll test it on ia32 and
x64.  Also,
this can be a ToRegister(left)  (fixed).

http://codereview.chromium.org/7489045/

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