If a function contains more than a certain number of locals (IA32: 9, X64: 6, ARM: 4)
a loop for initializing the locals with 'undefined' is more compact.
For less locals we unroll that loop by emitting a sequence of push instructions.
Review URL: http://codereview.chromium.org/515012
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3521 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This change fixes the problem with the original version of this approach
(r3032) that may lead to a corrupted stack if we would invoke spilling during
syncing a large SMI constant (unsafe SMIs) in the virtual frame.
The new code for storing unsafe SMI constants does not use an extra temporary
register. This prevents the compiler from ever having to spill during a
virutal frame sync operation.
For storing a large SMI constant we previously generated:
mov ecx, (large_smi & 0x0000ffff)
xor ecx, (large_smi & 0xffff0000)
push ecx
we now generate:
push (large_smi & 0x0000ffff)
or [esp], (large_smi & 0xffff0000)
Not using a temporary register avoids spilling within an nvocation
of VirtualFrame::SyncRange.
Review URL: http://codereview.chromium.org/391079
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3313 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
called from within a loop or not. In the past we lost the
information if a call site went megamorphic before a lazily
compiled callee was called for the first time. Now we track
that correctly (this is an issue that affects richards).
We still don't manage to track the in-loop state through a
constructor call, since constructor calls use LoadICs instead
of CallICs. This issue affects delta-blue. So in this patch
we assume that lazy compilations that don't happen through a
CallIC happen from inside a loop. I have an idea to fix this
but this patch is big enough already.
With our improved tracking of in-loop state I have switched
off the inlining of in-object loads for code that is not in
a loop. This benefits compile speed. One issue is that
eagerly compiled code now doesn't get the in-object loads
inlined. We need to eagerly compile less code to fix this.
Review URL: http://codereview.chromium.org/115744
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2046 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This issue was raised by Brett Wilson while reviewing my changelist for readability. Craig Silverstein (one of C++ SG maintainers) confirmed that we should declare one namespace per line. Our way of namespaces closing seems not violating style guides (there is no clear agreement on it), so I left it intact.
Review URL: http://codereview.chromium.org/115756
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2038 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
The function that prepares a virtual frame slot for writing (in order
to preserve the copy-on-write semantics of aliased frame elements) can
allocate registers, which may spill one from the frame. If we're
unlucky, the spilled register can be the source register for the frame
element write. In that case, ensure we do the write from memory.
Review URL: http://codereview.chromium.org/115125
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1904 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
stack pointer to change by more than one in a corner case. If we push
a constant smi larger than 16 bits, we push it via a temporary
register. Allocating the temporary can cause a register to be spilled
from the frame somewhere above the stack pointer.
As a fix, do not use pushes to materialize ranges of elements of size
larger than one.
Review URL: http://codereview.chromium.org/92121
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1785 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
