X64: Added implementations of Set(..., Immediate) to macro assembler.

X64: Added implementations of Set(..., Immediate) to macro assembler.
Removed duplicates comments in assembler-x64.cc.

[Lasse Reichstein, 2009-06-02 11:08:57]

Small review.

[William Hesse, 2009-06-02 13:21:58]

LGTM, with comments.

http://codereview.chromium.org/119035/diff/1/5
File src/x64/assembler-x64.h (right):

http://codereview.chromium.org/119035/diff/1/5#newcode47
Line 47: static const unsigned int kUInt32Mask = 0xffffffff;
Please use the V8_UINT64_C() macro to define a 64-bit mask.  Relying on the fact
that it gets extended to 64 bits from an unsigned is confusing.

In fact, for consistency, copy the is_intn and is_uintn functions from
assembler.h, using 64-bit types.  Either instantiate is_uint32 directly, or
rename is_uintn to is_uint64n, since you can't overload on integer type
reliably, I think.

http://codereview.chromium.org/119035/diff/1/6
File src/x64/macro-assembler-x64.cc (right):

http://codereview.chromium.org/119035/diff/1/6#newcode56
Line 56: movq(dst, x, RelocInfo::NONE);
Let's put a warning here, at least until we see if people need this.  A default
Relocation mode of NONE is unsafe, unless we know that people really will have
64-bit integers that are not coming from pointers.  Since the argument has
integer type, rather than pointer type, it might be OK to have that default mode
here, but I was intending for all relocation modes to be explicit.

[William Hesse, 2009-06-03 10:36:09]

http://codereview.chromium.org/119035/diff/1/5
File src/x64/assembler-x64.h (right):

http://codereview.chromium.org/119035/diff/1/5#newcode877
Line 877: inline void emit_rex_32(const Operand &);
Operand&, not Operand &