linear scan reg alloc. This fixes a problem I ran into where extracting
a function from a larger file caused the generated code to change (masking
the problem I was trying to debug) because the allocator behaved differently.
This changes the results for two X86 regression checks. stack-color-with-reg
is improved, with one less instruction, but pr3495 is worse, with one more
copy. As far as I can tell, these tests were just getting lucky or unlucky,
so I've changed the expected results.
llvm-svn: 81060
supporting other targets. Changed the code to pass MCAsmInfo to the parser
and the lexer. Then changed the lexer to use CommentString from MCAsmInfo
instead of a literal '#' character.
llvm-svn: 81046
a new class, MachineInstrIndex, which hides arithmetic details from
most clients. This is a step towards allowing the register allocator
to update/insert code during allocation.
llvm-svn: 81040
Constant uniquing tables. This allows distinct ConstantExpr objects
with the same operation and different flags.
Even though a ConstantExpr "a + b" is either always overflowing or
never overflowing (due to being a ConstantExpr), it's still necessary
to be able to represent it both with and without overflow flags at
the same time within the IR, because the safety of the flag may
depend on the context of the use. If the constant really does overflow,
it wouldn't ever be safe to use with the flag set, however the use
may be in code that is never actually executed.
This also makes it possible to merge all the flags tests into a single test.
llvm-svn: 80998
There's a bug with ocamlc that uses "char*" instead of "const char*" for
global string variables. This causes g++ to be very noisy when linking
ocamlc programs. That's why the ocaml test used to cat to /dev/null.
ocamlopt doesn't have this problem, so we can get rid of the >/dev/null,
which may obscure some problems.
llvm-svn: 80968
D test/Analysis/Profiling
--- Reverse-merging r80907 into '.':
U lib/Analysis/ProfileInfoLoaderPass.cpp
Attempt to remove failure in the self-hosting build bot.
llvm-svn: 80966
and exact flags. Because ConstantExprs are uniqued, creating an
expression with this flag causes all expressions with the same operands
to have the same flag, which may not be safe. Add, sub, mul, and sdiv
ConstantExprs are usually folded anyway, so the main interesting flag
here is inbounds, and the constant folder already knows how to set the
inbounds flag automatically in most cases, so there isn't an urgent need
for the API support.
This can be reconsidered in the future, but for now just removing these
API bits eliminates a source of potential trouble with little downside.
llvm-svn: 80959
Add or Remove operation complete, and not while building the intermediate tree.
This trades a little bit more memory usage for less accesses to the FoldingSet. On a benchmark for the clang static analyzer, this shaves off another 13% of execution time when using field/array sensitivity.
llvm-svn: 80955
for the complicated case where one register is tied to multiple destinations.
This avoids the extra scan of instruction operands that was introduced by
my recent change. I also pulled some code out into a separate
TryInstructionTransform method, added more comments, and renamed some
variables.
Besides all those changes, this takes care of a FIXME in the code regarding
an assumption about there being a single tied use of a register when
converting to a 3-address form. I'm not aware of cases where that assumption
is violated, but the code now only attempts to transform an instruction,
either by commuting its operands or by converting to a 3-address form,
for the simple case where there is a single pair of tied operands.
llvm-svn: 80945
