X64 implementation: if-then-else

X64 implementation: if-then-else

Committed: http://code.google.com/p/v8/source/detail?r=2229

[William Hesse, 2009-06-20 18:38:49]

If statement compiles, runs, and works correctly in one simple test case.

[Lasse Reichstein, 2009-06-22 07:47:45]

LGTM (but I don't completely understand how the compiler works).

http://codereview.chromium.org/141030/diff/1/6
File src/x64/codegen-x64.cc (right):

http://codereview.chromium.org/141030/diff/1/6#newcode1170
Line 1170: frame_->Push(&value);  // Undo the Pop() from above.
Would it be faster to inline the remaining three false cases (null, NaN and
empty string)? Or is the code for that too big to be inlined?

[William Hesse, 2009-06-22 08:06:58]

http://codereview.chromium.org/141030/diff/1/6
File src/x64/codegen-x64.cc (right):

http://codereview.chromium.org/141030/diff/1/6#newcode1170
Line 1170: frame_->Push(&value);  // Undo the Pop() from above.
On 2009/06/22 07:47:45, Lasse Reichstein wrote:
> Would it be faster to inline the remaining three false cases (null, NaN and
> empty string)? Or is the code for that too big to be inlined?

I count more cases: null, undetectable, empty string, NaN, +0, -0.  It is a lot
of code, and I think these cases aren't hit as often.