avoid reloads by reusing clobbered registers.
This was causing issues in 256.bzip2 when compiled with PIC for
a while (starting at r78217), though the problem has since been masked.
llvm-svn: 80872
When undoing a reuse in ReuseInfo::GetRegForReload, check if it was only a
sub-register being used. The MachineOperand::getSubReg() method is only valid
for virtual registers, so we have to recover the sub-register index manually.
llvm-svn: 79855
In the included test case, a stack load was not included in DistanceMap. That
caused TransferDeadness to ignore the instruction, leading to a scavenger
assert.
llvm-svn: 79090
- Some clients which used DOUT have moved to DEBUG. We are deprecating the
"magic" DOUT behavior which avoided calling printing functions when the
statement was disabled. In addition to being unnecessary magic, it had the
downside of leaving code in -Asserts builds, and of hiding potentially
unnecessary computations.
llvm-svn: 77019
This is considered a workaround. The problem is some targets are not modeling side effects correctly. PPC is apparently one of those. This patch allows ppc llvm-gcc to bootstrap on Darwin. Once we find out which instruction definitions are wrong, we can remove the PPCInstrInfo workaround.
llvm-svn: 76703
This adds location info for all llvm_unreachable calls (which is a macro now) in
!NDEBUG builds.
In NDEBUG builds location info and the message is off (it only prints
"UREACHABLE executed").
llvm-svn: 75640
Make llvm_unreachable take an optional string, thus moving the cerr<< out of
line.
LLVM_UNREACHABLE is now a simple wrapper that makes the message go away for
NDEBUG builds.
llvm-svn: 75379
The register allocator, when it allocates a register to a virtual register defined by an implicit_def, can allocate any physical register without worrying about overlapping live ranges. It should mark all of operands of the said virtual register so later passes will do the right thing.
This is not the best solution. But it should be a lot less fragile to having the scavenger try to track what is defined by implicit_def.
llvm-svn: 74518
