7 Commits

Author SHA1 Message Date
Jim Grosbach
ff8f931bbf Add materialization of virtual base registers for frame indices allocated into
the local block. Resolve references to those indices to a new base register.
For simplification and testing purposes, a new virtual base register is
allocated for each frame index being resolved. The result is truly horrible,
but correct, code that's good for exercising the new code paths.

Next up is adding thumb1 support, which should be very simple. Following that
will be adding base register re-use and implementing a reasonable ARM
heuristic for when a virtual base register should be generated at all.

llvm-svn: 111315
2010-08-17 22:41:55 +00:00
Jim Grosbach
23003dc92f silence warning
llvm-svn: 111274
2010-08-17 20:21:30 +00:00
Jim Grosbach
4597437c58 Add hook to examine an instruction referencing a frame index to determine
whether to allocate a virtual frame base register to resolve the frame
index reference in it. Implement a simple version for ARM to aid debugging.

In LocalStackSlotAllocation, scan the function for frame index references
to local frame indices and ask the target whether to allocate virtual
frame base registers for any it encounters. Purely infrastructural for
debug output. Next step is to actually allocate base registers, then add
intelligent re-use of them.

rdar://8277890

llvm-svn: 111262
2010-08-17 18:13:53 +00:00
Jim Grosbach
9e252e854d tidy up. remove unused local.
llvm-svn: 111206
2010-08-16 23:26:09 +00:00
Jim Grosbach
ea414d3999 Better handle alignment requirements for local objects in pre-regalloc frame
mapping. Have the local block track its alignment requirement, and then
apply that when the block itself is allocated. Previously, offsets could
get adjusted in PEI to be different, relative to one another, than the
block allocation thought they would be, which defeats the point of doing
the allocation this way. Continuing rdar://8277890

llvm-svn: 111197
2010-08-16 22:30:41 +00:00
Jim Grosbach
33f86ffe9f track local frame size in MFI, not local to the pass, since PEI needs it.
llvm-svn: 111164
2010-08-16 18:06:15 +00:00
Jim Grosbach
a4d3174cba Add a local stack object block allocation pass. This is still an
experimental pass that allocates locals relative to one another before
register allocation and then assigns them to actual stack slots as a block
later in PEI. This will eventually allow targets with limited index offset
range to allocate additional base registers (not just FP and SP) to
more efficiently reference locals, as well as handle situations where
locals cannot be referenced via SP or FP at all (dynamic stack realignment
together with variable sized objects, for example). It's currently
incomplete and almost certainly buggy. Work in progress.

Disabled by default and gated via the -enable-local-stack-alloc command
line option.

rdar://8277890

llvm-svn: 111059
2010-08-14 00:15:52 +00:00