Make appending var linking less of a special case.
It has to be a bit special because:
* materializeInitFor is not really supposed to call replaceAllUsesWith.
The caller has a plain variable with Dst and expects just the
initializer to be set, not for it to be removed.
* Calling mutateType as we used to do before gets some type
inconsistency which breaks the bitcode writer.
* If linkAppendingVarProto create a dest decl with the correct type to
avoid the above problems, it needs to put the original dst init in
some side table for materializeInitFor to use.
In the end the simplest solution seems to be to just have
linkAppendingVarProto do all the work and set ValueMap[SrcGV to avoid
recursion.
The difference is that now we don't error on out-of-comdat access to
internal global values. We copy them instead. This seems to match the
expectation of COFF linkers (see pr25686).
Original message:
Start deciding earlier what to link.
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.
Yury Gribov [Tue, 1 Dec 2015 11:40:55 +0000 (11:40 +0000)]
Introduce new @llvm.get.dynamic.area.offset.i{32, 64} intrinsics.
The @llvm.get.dynamic.area.offset.* intrinsic family is used to get the offset
from native stack pointer to the address of the most recent dynamic alloca on
the caller's stack. These intrinsics are intendend for use in combination with
@llvm.stacksave and @llvm.restore to get a pointer to the most recent dynamic
alloca. This is useful, for example, for AddressSanitizer's stack unpoisoning
routines.
Cong Hou [Tue, 1 Dec 2015 11:05:39 +0000 (11:05 +0000)]
Allow known and unknown probabilities coexist in MBB's successor list.
Previously it is not allowed for each MBB to have successors with both known and
unknown probabilities. However, this may be too strict as at this stage we could
not always guarantee that. It is better to remove this restriction now, and I
will work on validating MBB's successors' probabilities first (for example,
check if the sum is approximate one).
The Statistical Profiling Extension is an optional extension to
ARMv8.2-A. Since it is an optional extension, I have added the
FeatureSPE subtarget feature to control it. The assembler-visible parts
of this extension are the new "psb csync" instruction, which is
equivalent to "hint #17", and a number of system registers.
Oliver Stannard [Tue, 1 Dec 2015 10:23:06 +0000 (10:23 +0000)]
[ARM] Add subtarget features for ARMv8.2-A
This adds subtarget features for ARMv8.2-A, which builds on (and
requires the features from) ARMv8.1-A. Most assembler-visible features
of ARMv8.2-A are system instructions, and are all required parts of the
architecture, so just depend on the HasV8_2aOps subtarget feature.
There is also one large, optional feature, which adds 16-bit floating
point versions of all existing floating-point instructions (VFP and
SIMD), this is represented by the FeatureFullFP16 subtarget feature.
Craig Topper [Tue, 1 Dec 2015 06:13:16 +0000 (06:13 +0000)]
[X86] Fix patterns for memory forms of FP FSUBR and FDIVR. They need to have memory on the left hand side of the fsub/fdiv operations in their patterns.
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.
Craig Topper [Tue, 1 Dec 2015 06:13:04 +0000 (06:13 +0000)]
[Hexagon] Use ArrayRef to avoid needing to calculate an array size. Interestingly the original code may have had a bug because it was passing the byte size of a uint16_t array instead of the number of entries.
Cong Hou [Tue, 1 Dec 2015 05:29:22 +0000 (05:29 +0000)]
Replace all weight-based interfaces in MBB with probability-based interfaces, and update all uses of old interfaces.
(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.
(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)
Extend debug info for function parameters in SDAG.
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.
Cong Hou [Tue, 1 Dec 2015 00:02:51 +0000 (00:02 +0000)]
Replace all weight-based interfaces in MBB with probability-based interfaces, and update all uses of old interfaces.
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.
Simon Pilgrim [Mon, 30 Nov 2015 22:22:06 +0000 (22:22 +0000)]
[X86][FMA4] Prefer FMA4 to FMA
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.
Rafael Espindola [Mon, 30 Nov 2015 22:01:43 +0000 (22:01 +0000)]
Start deciding earlier what to link.
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.
Matt Arsenault [Mon, 30 Nov 2015 21:16:03 +0000 (21:16 +0000)]
AMDGPU: Rework how private buffer passed for HSA
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.
Matt Arsenault [Mon, 30 Nov 2015 21:15:53 +0000 (21:15 +0000)]
AMDGPU: Remove SIPrepareScratchRegs
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.
David Majnemer [Mon, 30 Nov 2015 19:04:19 +0000 (19:04 +0000)]
[X86] Add RIP to GR64_TCW64
The MachineVerifier wants to check that the register operands of an
instruction belong to the instruction's register class. RIP-relative
control flow instructions violated this by referencing RIP. While this
was fixed for SysV, it was never fixed for Win64.
Zoran Jovanovic [Mon, 30 Nov 2015 12:56:18 +0000 (12:56 +0000)]
[mips][microMIPS] Fix issue with offset operand of BALC and BC instructions
Value of offset operand for microMIPS BALC and BC instructions is currently shifted 2 bits, but it should be 1 bit.
Differential Revision: http://reviews.llvm.org/D14770
Daniel Sanders [Mon, 30 Nov 2015 09:52:00 +0000 (09:52 +0000)]
[mips][ias] Removed MSA instructions from base architecture valid-xfail.s's.
valid-xfail.s is for instructions that should be valid in the given ISA but
incorrectly fail. MSA instructions are correct to fail since MSA is not enabled.
Craig Topper [Mon, 30 Nov 2015 00:13:24 +0000 (00:13 +0000)]
[AVX512] The vpermi2 instructions require an integer vector for the index vector. This is reflected correctly in the intrinsics, but was not refelected in the isel patterns.
For the floating point types, this requires adding a bitcast to the index vector when its passed through to the output.
This one is enabled only under -ffast-math. There are cases where the
difference between the value computed and the correct value is huge
even for ffast-math, e.g. as Steven pointed out:
x = -1, y = -4
log(pow(-1), 4) = 0
4*log(-1) = NaN
I checked what GCC does and apparently they do the same optimization
(which result in the dramatic difference). Future work might try to
make this (slightly) less worse.