Not sure how to test this. I noticed by inspection in the isel tables where the same pattern tried to produce DIV and DIVR or SUB and SUBR.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254388 91177308-0d34-0410-b5e6-96231b3b80d8
(This is the second attempt to submit this patch. The first caused two assertion
failures and was reverted. See https://llvm.org/bugs/show_bug.cgi?id=25687)
The patch in http://reviews.llvm.org/D13745 is broken into four parts:
1. New interfaces without functional changes (http://reviews.llvm.org/D13908).
2. Use new interfaces in SelectionDAG, while in other passes treat probabilities
as weights (http://reviews.llvm.org/D14361).
3. Use new interfaces in all other passes.
4. Remove old interfaces.
This patch is 3+4 above. In this patch, MBB won't provide weight-based
interfaces any more, which are totally replaced by probability-based ones.
The interface addSuccessor() is redesigned so that the default probability is
unknown. We allow unknown probabilities but don't allow using it together
with known probabilities in successor list. That is to say, we either have a
list of successors with all known probabilities, or all unknown
probabilities. In the latter case, we assume each successor has 1/N
probability where N is the number of successors. An assertion checks if the
user is attempting to add a successor with the disallowed mixed use as stated
above. This can help us catch many misuses.
All uses of weight-based interfaces are now updated to use probability-based
ones.
Differential revision: http://reviews.llvm.org/D14973
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254377 91177308-0d34-0410-b5e6-96231b3b80d8
Nobody was checking the returnvalue of recede()/advance() so we can
simply replace this code with asserts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254371 91177308-0d34-0410-b5e6-96231b3b80d8
and the follow-up r254356: "Fix a bug in MachineBlockPlacement that may cause assertion failure during BranchProbability construction."
Asserts were firing in Chromium builds. See PR25687.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254366 91177308-0d34-0410-b5e6-96231b3b80d8
The root cause is the rounding behavior in BranchProbability construction. We may consider to use truncation instead in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254356 91177308-0d34-0410-b5e6-96231b3b80d8
This just concatenates the common DWP sections without doing any of the
fancy DWP things like:
1) update str_offsets
2) deduplicating strings
3) merging/creating cu/tu_index
Patches for these will follow shortly.
(also not sure about target triple/object file type for this tool - do I
really need a whole triple just to write an object file that contains
purely static/hardcoded bytes in each section? & I guess I should just
pick it based on the first input, maybe, rather than hardcoding for now
- but we only produce .dwo on ELF platforms with objcopy for now anyway)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254355 91177308-0d34-0410-b5e6-96231b3b80d8
SDAG currently can emit debug location for function parameters when
an llvm.dbg.declare points to either a function argument SSA temp,
or to an AllocaInst. This change extends this logic by adding a
fallback case when neither of the above is true.
This is required for SafeStack, which may copy the contents of a
byval function argument into something that is not an alloca, and
then describe the target as the new location of the said argument.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254352 91177308-0d34-0410-b5e6-96231b3b80d8
The current code does not take alloca array size into account and,
as a result, considers any access past the first array element to be
unsafe.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254350 91177308-0d34-0410-b5e6-96231b3b80d8
The patch in http://reviews.llvm.org/D13745 is broken into four parts:
1. New interfaces without functional changes (http://reviews.llvm.org/D13908).
2. Use new interfaces in SelectionDAG, while in other passes treat probabilities
as weights (http://reviews.llvm.org/D14361).
3. Use new interfaces in all other passes.
4. Remove old interfaces.
This patch is 3+4 above. In this patch, MBB won't provide weight-based
interfaces any more, which are totally replaced by probability-based ones.
The interface addSuccessor() is redesigned so that the default probability is
unknown. We allow unknown probabilities but don't allow using it together
with known probabilities in successor list. That is to say, we either have a
list of successors with all known probabilities, or all unknown
probabilities. In the latter case, we assume each successor has 1/N
probability where N is the number of successors. An assertion checks if the
user is attempting to add a successor with the disallowed mixed use as stated
above. This can help us catch many misuses.
All uses of weight-based interfaces are now updated to use probability-based
ones.
Differential revision: http://reviews.llvm.org/D14973
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254348 91177308-0d34-0410-b5e6-96231b3b80d8
We currently output FMA instructions on targets which support both FMA4 + FMA (i.e. later Bulldozer CPUS bdver2/bdver3/bdver4).
This patch flips this so FMA4 is preferred; this is for several reasons:
1 - FMA4 is non-destructive reducing the need for mov instructions.
2 - Its more straighforward to commute and fold inputs (although the recent work on FMA has reduced this difference).
3 - All supported targets have FMA4 performance equal or better to FMA - Piledriver (bdver2) in particular has half the throughput when executing FMA instructions.
Its looks like no future AMD processor lines will support FMA4 after the Bulldozer series so we're not causing problems for later CPUs.
Differential Revision: http://reviews.llvm.org/D14997
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254339 91177308-0d34-0410-b5e6-96231b3b80d8
A traditional linker is roughly split in symbol resolution and "copying
stuff".
The two tasks are badly mixed in lib/Linker.
This starts splitting them apart.
With this patch there are no direct call to linkGlobalValueBody or
linkGlobalValueProto. Everything is linked via WapValue.
This also includes a few fixes:
* A GV goes undefined if the comdat is dropped (comdat11.ll).
* We error if an internal GV goes undefined (comdat13.ll).
* We don't link an unused comdat.
The first two match the behavior of an ELF linker. The second one is
equivalent to running globaldce on the input.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254336 91177308-0d34-0410-b5e6-96231b3b80d8
If we know we have stack objects, we reserve the registers
that the private buffer resource and wave offset are passed
and use them directly.
If not, reserve the last 5 SGPRs just in case we need to spill.
After register allocation, try to pick the next available registers
instead of the last SGPRs, and then insert copies from the inputs
to the reserved registers in the progloue.
This also only selectively enables all of the input registers
which are really required instead of always enabling them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254331 91177308-0d34-0410-b5e6-96231b3b80d8
It does not work because of emergency stack slots.
This pass was supposed to eliminate dummy registers for the
spill instructions, but the register scavenger can introduce
more during PrologEpilogInserter, so some would end up
left behind if they were needed.
The potential for spilling the scratch resource descriptor
and offset register makes doing something like this
overly complicated. Reserve registers to use for the resource
descriptor and use them directly in eliminateFrameIndex.
Also removes creating another scratch resource descriptor
when directly selecting scratch MUBUF instructions.
The choice of which registers are reserved is temporary.
For now it attempts to pick the next available registers
after the user and system SGPRs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254329 91177308-0d34-0410-b5e6-96231b3b80d8
