is determined by whether the node has a Flag operand. However, if the
node does have a Flag operand, it will be glued to its register's
def, so the heuristic would end up spuriously applying to whatever
node is the def.
llvm-svn: 64319
It was transforming (x&y)==y to (x&y)!=0 in the case where
y is variable and known to have at most one bit set (e.g. z&1).
This is not correct; the expressions are not equivalent when y==0.
I believe this patch salvages what can be salvaged, including
all the cases in bt.ll. Dan, please review.
Fixes gcc.c-torture/execute/20040709-[12].c
llvm-svn: 64314
instruction index across each part. Instruction indices are used
to make live range queries, and live ranges can extend beyond
scheduling region boundaries.
Refactor the ScheduleDAGSDNodes class some more so that it
doesn't have to worry about this additional information.
llvm-svn: 64288
a scheduling region boundary. This isn't necessary for
correctness; it helps with compile time, as it avoids the need
for data- and anti-dependencies from all spills and reloads on
the stack-pointer modification.
llvm-svn: 64255
scheduling, and generalize is so that preserves state across
scheduling regions. This fixes incorrect live-range information around
terminators and labels, which are effective region boundaries.
In place of looking for terminators to anchor inter-block dependencies,
introduce special entry and exit scheduling units for this purpose.
llvm-svn: 64254
suprise to some callers, e.g. register coalescer. For now, add an parameter
that tells AnalyzeBranch whether it's safe to modify the mbb. A better
solution is out there, but I don't have time to deal with it right now.
llvm-svn: 64124
Right now if the coalesced copy def is dead and its src is a kill, and that
there are now other uses within the live range, the coalescer would mark the
def of the source register as dead. But it should also check if there are
other kills which means the value has other uses not in the live range.
llvm-svn: 64075
Adjust derived classes to pass UnknownLoc where
a DebugLoc does not make sense. Pick one of
DebugLoc and non-DebugLoc variants to survive
for all such classes.
llvm-svn: 64000
Many targets build placeholder nodes for special operands, e.g.
GlobalBaseReg on X86 and PPC for the PIC base. There's no
sensible way to associate debug info with these. I've left
them built with getNode calls with explicit DebugLoc::getUnknownLoc operands.
I'm not too happy about this but don't see a good improvement;
I considered adding a getPseudoOperand or something, but it
seems to me that'll just make it harder to read.
llvm-svn: 63992
SelectionDAGISel::CreateScheduler, and make it just create the
scheduler. Leave running the scheduler to the higher-level code.
This makes the higher-level code a little more explicit and
easier to follow, and will help enable some future refactoring.
llvm-svn: 63944
that used this header to select a scheduling policy should
use SchedulerRegistry.h instead (llvm-gcc and clang were
updated a while ago).
llvm-svn: 63934
Evan Cheng