registers that alias Reg, including itself. This is almost the same as the
existing getAliasSet() method, except for the inclusion of Reg.
The name matches the reflexive TRI::regsOverlap(x, y) relation.
It is very common to do stuff to a register and all its aliases:
stuff(Reg)
for (const unsigned *Alias = TRI->getAliasSet(Reg); *Alias; ++Alias)
stuff(*Alias);
That can now be written as the simpler:
for (const unsigned *Alias = TRI->getOverlaps(Reg); *Alias; ++Alias)
stuff(*Alias);
This change requires a bit more constant space for the alias lists because Reg
is included and because the empty alias list cannot be shared any longer.
If the getAliasSet method is eventually removed, this space can be reclaimed by
sharing overlap lists. For instance, %rax and %eax have identical overlap sets.
llvm-svn: 121800
AliasAnalysis consumers, PartialAlias will be treated as MayAlias.
For AliasAnalysis chaining, MayAlias says "procede to the next analysis".
PartialAlias will be used to indicate that the query should terminate,
even though it didn't reach MustAlias or NoAlias.
llvm-svn: 121507
the offset. Add a new fixup flag to represent this, and use it for the one fixups that I have a testcase for needing
this. It's quite likely that the other Thumb fixups will need this too, and to have their fixup encoding logic
adjusted accordingly.
llvm-svn: 121408
both forward and backward scheduling. Rename it to
ScoreboardHazardRecognizer (Scoreboard is one word). Remove integer
division from the scoreboard's critical path.
llvm-svn: 121274
This new register allocator is initially identical to RegAllocBasic, but it will
receive all of the tricks that RegAllocBasic won't get.
RegAllocGreedy will eventually replace linear scan.
llvm-svn: 121234
before:
4 assembler - Number of assembler layout and relaxation steps
78563 assembler - Number of emitted assembler fragments
8693904 assembler - Number of emitted object file bytes
271223 assembler - Number of evaluated fixups
330771677 assembler - Number of fragment layouts
5958 assembler - Number of relaxed instructions
2508361 mcexpr - Number of MCExpr evaluations
real 0m26.123s
user 0m25.694s
sys 0m0.388s
after:
4 assembler - Number of assembler layout and relaxation steps
78563 assembler - Number of emitted assembler fragments
8693904 assembler - Number of emitted object file bytes
271223 assembler - Number of evaluated fixups
231507 assembler - Number of fragment layouts
5958 assembler - Number of relaxed instructions
2508361 mcexpr - Number of MCExpr evaluations
real 0m2.500s
user 0m2.113s
sys 0m0.273s
And yes, the outputs are identical :-)
llvm-svn: 121207
zextOrTrunc(), and APSInt methods extend(), extOrTrunc() and new method
trunc(), to be const and to return a new value instead of modifying the
object in place.
llvm-svn: 121120
actuall addresses in a .o file, so it is better to let the MachO writer compute
it.
This is good for two reasons. First, areas that shouldn't care about
addresses now don't have access to it. Second, the layout of each section
is independent. I should use this in a subsequent commit to speed it up.
Most of the patch is just removing the section address computation. The two
interesting parts are the change on how we handle padding in the end
of sections and how MachO can get the address of a-b when a and b are in
different sections.
Since now the expression evaluation normally doesn't know the section address,
it will think that a-b needs relocation and let the MachO writer know. Once
it has computed the section addresses, it calls back the expression evaluation
with the section addresses to resolve these expressions.
The remaining problem is the handling of padding. Currently it will create
a special alignment fragment at the end. Since that fragment doesn't update
the alignment of the section, it needs the real address to be computed.
Since now the layout will not compute a-b with a and b in different sections,
the only effect that the special alignment fragment has is update the
address size of the section. This can also be done by the MachO writer.
llvm-svn: 121076
Jakob Stoklund Olesen