Re-commit r303937 + r303949 as they were not the cause for the build
failures.
We do not track liveness of reserved registers so adding them to the
liveins list in computeLiveIns() was completely unnecessary.
llvm-svn: 303970
findScratchNonCalleeSaveRegister() just needs a simple liveness
analysis, use LivePhysRegs for that as it is simpler and does not depend
on the kill flags.
This commit adds a convenience function available() to LivePhysRegs:
This function returns true if the given register is not reserved and
neither the register nor any of its aliases are alive.
Differential Revision: http://reviews.llvm.org/D21865
llvm-svn: 274685
Remove the AddPristinesAndCSRs parameters from
addLiveIns()/addLiveOuts().
We need to respect pristine registers after prologue epilogue insertion,
Seeing that we got this wrong in at least two commits already, we should
rather pay the small price to query MachineFrameInfo for it.
There are three cases that did not set AddPristineAndCSRs to true even
after register allocation:
- ExecutionDepsFix: live-out registers are used as a hint that the
register is used soon. This is not true for pristine registers so
use the new addLiveOutsNoPristines() to maintain this behaviour.
- SystemZShortenInst: Not setting AddPristineAndCSRs to true looks like
a bug, should do the right thing automatically now.
- StackMapLivenessAnalysis: Not adding pristine registers looks like a
bug to me. Added a FIXME comment but maintain the current behaviour
as a change may need to get coordinated with GC runtimes.
llvm-svn: 268336
We must remove all aliased registers which may be more than the all sub
and super registers combined.
Bug found while reading the code. The bug does not affect any existing
target as the only use of register aliases I could found were control
registers on ARM and Hexagon which are all reserved.
llvm-svn: 265510
I realized that the live-out set computed for the return block is
missing the callee saved registers (the non-pristine ones to be exact).
This only affects the liveness computed for instructions inside the
function epilogue which currently none of the LivePhysRegs users in llvm
cares about, so this is just a drive-by fix without a testcase.
Differential Revision: http://reviews.llvm.org/D13180
llvm-svn: 248636
Note, this is a reapplication of r236515 with a fix to not assert on non-register operands, but instead only handle them until the subsequent commit. Original commit message follows.
The code was basically the same here already. Just added an out parameter for a vector of seen defs so that UpdatePredRedefs can call StepForward first, then do its own post processing on the seen defs.
Will be used in the next commit to also handle regmasks.
llvm-svn: 236538
The code was basically the same here already. Just added an out parameter for a vector of seen defs so that UpdatePredRedefs can call StepForward first, then do its own post processing on the seen defs.
Will be used in the next commit to also handle regmasks.
llvm-svn: 236514
Add header guards to files that were missing guards. Remove #endif comments
as they don't seem common in LLVM (we can easily add them back if we decide
they're useful)
Changes made by clang-tidy with minor tweaks.
llvm-svn: 215558