Changes related modules so VNInfo's are not copied. This decrease
copy coalescing time by 45% and overall compilation time by 10% on siod.
llvm-svn: 41579
simultaneously. Move that pass to SimpleRegisterCoalescing.
This makes it easier to implement alternative register allocation and
coalescing strategies while maintaining reuse of the existing live
interval analysis.
llvm-svn: 37520
- A register def / use now implicitly affects sub-register liveness but does
not affect liveness information of super-registers.
- Def of a larger register (if followed by a use later) is treated as
read/mod/write of a smaller register.
llvm-svn: 36434
long live interval that has low usage density.
1. Change order of coalescing to join physical registers with virtual
registers first before virtual register intervals become too long.
2. Check size and usage density to determine if it's worthwhile to join.
3. If joining is aborted, assign virtual register live interval allocation
preference field to the physical register.
4. Register allocator should try to allocate to the preferred register
first (if available) to create identify moves that can be eliminated.
llvm-svn: 36218
- When coalescing a copy MI, if its destination is "dead", propagate the
property to the source MI's destination if there are no intervening uses.
- Detect dead function live-in's and remove them.
llvm-svn: 34383
rework the hacks that had us passing OStream in. We pass in std::ostream*
instead, check for null, and then dispatch to the correct print() method.
llvm-svn: 32636
number of copies, potentially defining live ranges that appear to have
differing value numbers that become identical when coallsced. Among other
things, this fixes CodeGen/X86/shift-coalesce.ll and PR687.
llvm-svn: 29968
instructions which define each value#) to simplify and improve the coallescer.
In particular, this patch:
1. Implements iterative coallescing.
2. Reverts an unsafe hack from handlePhysRegDef, superceeding it with a
better solution.
3. Implements PR865, "coallescing" away the second copy in code like:
A = B
...
B = A
This also includes changes to symbolically print registers in intervals
when possible.
llvm-svn: 29862
targets to register custom legalizers for ConstantFP in case there isn't a
fixed list of constants that can be generated. On some architectures (ia64?)
all fp immediates are legal.
llvm-svn: 25769