Perform the following transformation:
| Before | After |
|------------------+---------------------|
| add w2, w0, w1 | adds w2, w0, w1 |
| cmp w2, #0x0 | b.<cond'> <addr> |
| b.<cond> <addr> | |
|------------------+---------------------|
| add w2, w0, w1 | adds w2, w0, w1 |
| cmp #0x0, w2 | b.<cond'> <addr> |
| b.<cond> <addr> | |
and the same for and instructions instead of add. When the result of the
add/and is not used, generate cmn/tst instead. We need to take care with which
conditions we can handle and what new condition we map them to.
BUG=
Review-Url: https://codereview.chromium.org/2065243005
Cr-Commit-Position: refs/heads/master@{#37400}
Sequences like:
1: Load[kRepWord32|kTypeInt32](<address>, ...)
2: Word32And(1, <constant>)
3: Word32Equal(2, <another constant>)
4: Store[(kRepWord32 : NoWriteBarrier)](<address>, <value>)
5: Branch[None](3, ...) -> B1, B2
where #1 and #4 refer to the same memory location, are problematic because in VisitBranch we assume that 'InstructionSelector::CanCover()' is transitive.
What happens is that CanCover(5, 3) is true (3 is a pure op), and so are CanCover(3, 2), CanCover(2, 1), but the effect level of 5 and 3 never gets checked because 3 is a pure op. Upon VisitBranch, we ended up materializing:
mov [address], <value>
test [address], <another constant>
With this patch, it becomes:
mov reg, [address]
mov [address], <value>
test reg, <another constant>
BUG=chromium:611976
Review-Url: https://codereview.chromium.org/2008493002
Cr-Commit-Position: refs/heads/master@{#36482}
MachineType is now a class with two enum fields:
- MachineRepresentation
- MachineSemantic
Both enums are usable on their own, and this change switches some places from using MachineType to use just MachineRepresentation. Most notably:
- register allocator now uses just the representation.
- Phi and Select nodes only refer to representations.
Review URL: https://codereview.chromium.org/1513543003
Cr-Commit-Position: refs/heads/master@{#32738}
This moves all cctest files for the compiler to live in the same
namespace as the components they are testing. Hence we can avoid the
forbidden using directives pulling in entire namespaces.
From the Google C++ style guide: "You may not use a using-directive to
make all names from a namespace available". This would be covered by
presubmit linter checks if build/namespaces were not blacklisted.
R=bmeurer@chromium.org
Review URL: https://codereview.chromium.org/1424943004
Cr-Commit-Position: refs/heads/master@{#31671}
TurboFan is now a requirement and supported by all backends, so we don't
need those macros (plus all the machinery on top) anymore.
R=jarin@chromium.org
Review URL: https://codereview.chromium.org/1282763002
Cr-Commit-Position: refs/heads/master@{#30082}
Use std::numeric_limits<double>::quiet_NaN() and
std::numeric_limits<float>::quiet_NaN() instead.
Review URL: https://codereview.chromium.org/864803002
Cr-Commit-Position: refs/heads/master@{#26195}
