http://codereview.chromium.org/545151/diff/1/2
File src/ia32/codegen-ia32.cc (right):
http://codereview.chromium.org/545151/diff/1/2#newcode8223
src/ia32/codegen-ia32.cc:8223: // Check for flat ascii cons string.
On 2010/01/21 13:20:56, Lasse Reichstein wrote:
Instead of testing for flat ASCII and Two-Byte strings independently,
could you
just test for a flat string (const string with second part being The
Empty
String), and then loop back to checking the representation and
encoding with the
first part?
Good point. Restructured the code to first check for seq string using
test(Operand(ebx),
Immediate(kIsNotStringMask | kStringRepresentationMask))
As kStringTag and kSeqStringTag are both zero and ump forward to seq
string code. Fall through to check for flat cons string and fall through
to seq string code if it is.
Seq string code handles both encodings.
http://codereview.chromium.org/545151/diff/1/2#newcode8224
src/ia32/codegen-ia32.cc:8224: __ cmp(ebx, kStringTag | kConsStringTag |
kAsciiStringTag);
On 2010/01/21 13:20:56, Lasse Reichstein wrote:
I.e., ignore the representation tag here, and just see if it's a cons
...
See above.
http://codereview.chromium.org/545151/diff/1/2#newcode8229
src/ia32/codegen-ia32.cc:8229: __ mov(eax, FieldOperand(eax,
ConsString::kFirstOffset));
On 2010/01/21 13:20:56, Lasse Reichstein wrote:
... and jump back to line 8209 here.
See above.
http://codereview.chromium.org/545151/diff/1/2#newcode8241
src/ia32/codegen-ia32.cc:8241: __ cmp(ebx, kStringTag | kConsStringTag |
kStringTag);
On 2010/01/21 13:20:56, Lasse Reichstein wrote:
Two occurrences of kStringTag and non of kTwoByteStringTag?
Fixed. Only worked becahse kTwoByteStringTag and kStringTag are both
zero.
http://codereview.chromium.org/545151/diff/1/2#newcode8261
src/ia32/codegen-ia32.cc:8261: __ mov(edx, FieldOperand(ecx,
JSRegExp::kDataAsciiCodeOffset));
On 2010/01/21 13:20:56, Lasse Reichstein wrote:
If we had the string's instance type here (I believe it's in ebc), we
could do
compute both the offset and the 0/1 for being two-byte from the type &
kStringEncodingMask (ASCII being 4 and UC16 being 0). It's probably
not a lot
shorter than having both branches of code, though.
But we could completely avoid checking the encoding above.
Decided not to try to compute the offset, that is did not want to do
ASSERT_EQ(kAsciiStringTag == (JSRegExp::kDataUC16CodeOffset -
JSRegExp::kDataAsciiCodeOffset)).
http://codereview.chromium.org/545151/diff/1/2#newcode8275
src/ia32/codegen-ia32.cc:8275: __ xor_(edi, Operand(edi)); // Type is
two byte.
On 2010/01/21 13:20:56, Lasse Reichstein wrote:
You can use __ Set(edi, Immediate(0)); to make this more readable. The
Set macro
uses xor if the argument is zero and mov if it's not.
Done.
http://codereview.chromium.org/545151/diff/1/2#newcode8276
src/ia32/codegen-ia32.cc:8276: __ jmp(&invoke_regexp);
On 2010/01/21 13:20:56, Lasse Reichstein wrote:
Should just fall through.
Done.
http://codereview.chromium.org/545151
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