Commit Graph

154 Commits

Author SHA1 Message Date
Shiva Chen 801bf7ebbe [DebugInfo] Examine all uses of isDebugValue() for debug instructions.
Because we create a new kind of debug instruction, DBG_LABEL, we need to
check all passes which use isDebugValue() to check MachineInstr is debug
instruction or not. When expelling debug instructions, we should expel
both DBG_VALUE and DBG_LABEL. So, I create a new function,
isDebugInstr(), in MachineInstr to check whether the MachineInstr is
debug instruction or not.

This patch has no new test case. I have run regression test and there is
no difference in regression test.

Differential Revision: https://reviews.llvm.org/D45342

Patch by Hsiangkai Wang.

llvm-svn: 331844
2018-05-09 02:42:00 +00:00
Francis Visoiu Mistrih c855e92ca9 [AArch64] Place the first ldp at the end when ReverseCSRRestoreSeq is true
Put the first ldp at the end, so that the load-store optimizer can run
and merge the ldp and the add into a post-index ldp.

This didn't work in case no frame was needed and resulted in code size
regressions.

llvm-svn: 331044
2018-04-27 15:30:54 +00:00
Geoff Berry 08ab8c9544 [AArch64] Fix scavenged spill slot base when stack realignment required.
Summary:
Use the FP for scavenged spill slot accesses to prevent corruption of
the callee-save region when the SP is re-aligned.

Based on problem and patch reported by @paulwalker-arm

This is an alternative to solution proposed in D45770

Reviewers: t.p.northover, paulwalker-arm, thegameg, javed.absar

Subscribers: qcolombet, mcrosier, paulwalker-arm, kristof.beyls, rengolin, javed.absar, llvm-commits

Differential Revision: https://reviews.llvm.org/D46063

llvm-svn: 330976
2018-04-26 18:50:45 +00:00
Jessica Paquette 8aa6cd5cb9 [AArch64] Move AFI->setRedZone(false) to top of emitPrologue
AFI->setRedZone(false) was put in the wrong place before, and so it only fired
on functions that didn't have stack frames. This moves that to the top of
emitPrologue to make sure that every function without a redzone has it set
correctly.

This also adds a function representing one of the early exit cases (GHC calling
convention) to the MachineOutliner noredzone test to ensure that we can outline
from functions like these, where we never use a redzone.

llvm-svn: 329922
2018-04-12 16:16:18 +00:00
Francis Visoiu Mistrih 6463922e3a [AArch64] Fix regression after r329691
In r329691, we would choose FP even if the offset wouldn't fit, just
because the offset is smaller than the one from BP. This made many
accesses through FP need to scavenge a register, which resulted in
slower and bigger code for no good reason.

This patch now always picks the offset that fits first, even if FP is
preferred.

llvm-svn: 329797
2018-04-11 12:36:55 +00:00
Francis Visoiu Mistrih f2c22050e8 [AArch64] Use FP to access the emergency spill slot
In the presence of variable-sized stack objects, we always picked the
base pointer when resolving frame indices if it was available.

This makes us hit an assert where we can't reach the emergency spill
slot if it's too far away from the base pointer. Since on AArch64 we
decide to place the emergency spill slot at the top of the frame, it
makes more sense to use FP to access it.

The changes here don't affect only emergency spill slots but all the
frame indices. The goal here is to try to choose between FP, BP and SP
so that we minimize the offset and avoid scavenging, or worse, asserting
when trying to access a slot allocated by the scavenger.

Previously discussed here: https://reviews.llvm.org/D40876.

Differential Revision: https://reviews.llvm.org/D45358

llvm-svn: 329691
2018-04-10 11:29:40 +00:00
Peter Collingbourne f11eb3ebe7 AArch64: Implement support for the shadowcallstack attribute.
The implementation of shadow call stack on aarch64 is quite different to
the implementation on x86_64. Instead of reserving a segment register for
the shadow call stack, we reserve the platform register, x18. Any function
that spills lr to sp also spills it to the shadow call stack, a pointer to
which is stored in x18.

Differential Revision: https://reviews.llvm.org/D45239

llvm-svn: 329236
2018-04-04 21:55:44 +00:00
Jessica Paquette 642f6c61a3 [MachineOutliner] Keep track of fns that use a redzone in AArch64FunctionInfo
This patch adds a hasRedZone() function to AArch64MachineFunctionInfo. It
returns true if the function is known to use a redzone, false if it is known
to not use a redzone, and no value otherwise.

This removes the requirement to pass -mno-red-zone when outlining for AArch64.

https://reviews.llvm.org/D45189

llvm-svn: 329120
2018-04-03 21:56:10 +00:00
Francis Visoiu Mistrih 164560bd74 [AArch64] Emit CSR loads in the same order as stores
Optionally allow the order of restoring the callee-saved registers in the
epilogue to be reversed.

The flag -reverse-csr-restore-seq generates the following code:

```
stp     x26, x25, [sp, #-64]!
stp     x24, x23, [sp, #16]
stp     x22, x21, [sp, #32]
stp     x20, x19, [sp, #48]

; [..]

ldp     x24, x23, [sp, #16]
ldp     x22, x21, [sp, #32]
ldp     x20, x19, [sp, #48]
ldp     x26, x25, [sp], #64
ret
```

Note how the CSRs are restored in the same order as they are saved.

One exception to this rule is the last `ldp`, which allows us to merge
the stack adjustment and the ldp into a post-index ldp. This is done by
first generating:

ldp x26, x27, [sp]
add sp, sp, #64

which gets merged by the arm64 load store optimizer into

ldp x26, x25, [sp], #64

The flag is disabled by default.

llvm-svn: 327569
2018-03-14 20:34:03 +00:00
Hans Wennborg 89c35fc44d Support for the mno-stack-arg-probe flag
Adds support for this flag. There is also another piece for clang
(separate review). More info:
https://bugs.llvm.org/show_bug.cgi?id=36221

By Ruslan Nikolaev!

Differential Revision: https://reviews.llvm.org/D43107

llvm-svn: 325900
2018-02-23 13:46:25 +00:00
Matthias Braun 5c290dc206 AArch64: Fix emergency spillslot being out of reach for large callframes
Re-commit of r322200: The testcase shouldn't hit machineverifiers
anymore with r322917 in place.

Large callframes (calls with several hundreds or thousands or
parameters) could lead to situations in which the emergency spillslot is
out of range to be addressed relative to the stack pointer.
This commit forces the use of a frame pointer in the presence of large
callframes.

This commit does several things:
- Compute max callframe size at the end of instruction selection.
- Add mirFileLoaded target callback. Use it to compute the max callframe size
  after loading a .mir file when the size wasn't specified in the file.
- Let TargetFrameLowering::hasFP() return true if there exists a
  callframe > 255 bytes.
- Always place the emergency spillslot close to FP if we have a frame
  pointer.
- Note that `useFPForScavengingIndex()` would previously return false
  when a base pointer was available leading to the emergency spillslot
  getting allocated late (that's the whole effect of this callback).
  Which made no sense to me so I took this case out: Even though the
  emergency spillslot is technically not referenced by FP in this case
  we still want it allocated early.

Differential Revision: https://reviews.llvm.org/D40876

llvm-svn: 322919
2018-01-19 03:16:36 +00:00
Matthias Braun e3a8db7ba1 Revert "AArch64: Fix emergency spillslot being out of reach for large callframes"
Revert for now as the testcase is hitting a pre-existing verifier error
that manifest as a failure when expensive checks are enabled (or
-verify-machineinstrs) is used.

This reverts commit r322200.

llvm-svn: 322231
2018-01-10 22:36:28 +00:00
Matthias Braun b42ffa1283 AArch64: Fix emergency spillslot being out of reach for large callframes
Large callframes (calls with several hundreds or thousands or
parameters) could lead to situations in which the emergency spillslot is
out of range to be addressed relative to the stack pointer.
This commit forces the use of a frame pointer in the presence of large
callframes.

This commit does several things:
- Compute max callframe size at the end of instruction selection.
- Add mirFileLoaded target callback. Use it to compute the max callframe size
  after loading a .mir file when the size wasn't specified in the file.
- Let TargetFrameLowering::hasFP() return true if there exists a
  callframe > 255 bytes.
- Always place the emergency spillslot close to FP if we have a frame
  pointer.
- Note that `useFPForScavengingIndex()` would previously return false
  when a base pointer was available leading to the emergency spillslot
  getting allocated late (that's the whole effect of this callback).
  Which made no sense to me so I took this case out: Even though the
  emergency spillslot is technically not referenced by FP in this case
  we still want it allocated early.

Differential Revision: https://reviews.llvm.org/D40876

llvm-svn: 322200
2018-01-10 18:16:24 +00:00
Martin Storsjo 2778fd0b59 [AArch64] Implement stack probing for windows
Differential Revision: https://reviews.llvm.org/D41131

llvm-svn: 321150
2017-12-20 06:51:45 +00:00
Matthias Braun f1caa2833f MachineFunction: Return reference from getFunction(); NFC
The Function can never be nullptr so we can return a reference.

llvm-svn: 320884
2017-12-15 22:22:58 +00:00
Francis Visoiu Mistrih c71cced0aa [CodeGen] Always use `printReg` to print registers in both MIR and debug
output

As part of the unification of the debug format and the MIR format,
always use `printReg` to print all kinds of registers.

Updated the tests using '_' instead of '%noreg' until we decide which
one we want to be the default one.

Differential Revision: https://reviews.llvm.org/D40421

llvm-svn: 319445
2017-11-30 16:12:24 +00:00
Francis Visoiu Mistrih 9d419d3b0c [CodeGen] Rename functions PrintReg* to printReg*
LLVM Coding Standards:
  Function names should be verb phrases (as they represent actions), and
  command-like function should be imperative. The name should be camel
  case, and start with a lower case letter (e.g. openFile() or isFoo()).

Differential Revision: https://reviews.llvm.org/D40416

llvm-svn: 319168
2017-11-28 12:42:37 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
David Blaikie 3f833edc7c Target/TargetInstrInfo.h -> CodeGen/TargetInstrInfo.h to match layering
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.

llvm-svn: 317647
2017-11-08 01:01:31 +00:00
Javed Absar d13d419d4a [AArch64]: range loopify frame-lowering
llvm-svn: 316960
2017-10-30 22:00:06 +00:00
Krzysztof Parzyszek bea30c6286 Add "Restored" flag to CalleeSavedInfo
The liveness-tracking code assumes that the registers that were saved
in the function's prolog are live outside of the function. Specifically,
that registers that were saved are also live-on-exit from the function.
This isn't always the case as illustrated by the LR register on ARM.

Differential Revision: https://reviews.llvm.org/D36160

llvm-svn: 310619
2017-08-10 16:17:32 +00:00
Martin Storsjo eacf4e408b [AArch64] Rewrite stack frame handling for win64 vararg functions
The previous attempt, which made do with a single offset in
computeCalleeSaveRegisterPairs, wasn't quite enough. The previous
attempt only worked as long as CombineSPBump == true (since the
offset would be adjusted later in fixupCalleeSaveRestoreStackOffset).

Instead include the size for the fixed stack area used for win64
varargs in calculations in emitPrologue/emitEpilogue. The stack
consists of mainly three parts;
- AFI->getLocalStackSize()
- AFI->getCalleeSavedStackSize()
- FixedObject

Most of the places in the code which previously used the CSStackSize
now use PrologueSaveSize instead, which is the sum of the latter
two, while some cases which need exactly the middle one use
AFI->getCalleeSavedStackSize() explicitly instead of a local variable.

In addition to moving the offsetting into emitPrologue/emitEpilogue
(which fixes functions with CombineSPBump == false), also set the
frame pointer to point to the right location, where the frame pointer
and link register actually are stored. In addition to the prologue/epilogue,
this also requires changes to resolveFrameIndexReference.

Add tests for a function that keeps a frame pointer and another one
that uses a VLA.

Differential Revision: https://reviews.llvm.org/D35919

llvm-svn: 309744
2017-08-01 21:13:54 +00:00
Martin Storsjo 2f24e93481 [AArch64] Extend CallingConv::X86_64_Win64 to AArch64 as well
Rename the enum value from X86_64_Win64 to plain Win64.

The symbol exposed in the textual IR is changed from 'x86_64_win64cc'
to 'win64cc', but the numeric value is kept, keeping support for
old bitcode.

Differential Revision: https://reviews.llvm.org/D34474

llvm-svn: 308208
2017-07-17 20:05:19 +00:00
Martin Storsjo 68266faa31 [AArch64] Implement support for windows style vararg functions
Pass parameters properly in calls to such functions (pass all
floats in integer registers), and handle va_start properly (allocate
stack immediately below the arguments on the stack, to save the
register arguments into a single continuous array).

Differential Revision: https://reviews.llvm.org/D35006

llvm-svn: 307928
2017-07-13 17:03:12 +00:00
Kristof Beyls 2af1e90eb2 Fix PR33031: correct the estimate of maximum offset for instructions spilling/filling the stack.
llvm-svn: 304196
2017-05-30 06:58:41 +00:00
Matthias Braun 88c8c9847d AArch64/PEI: Do not add reserved regs to liveins
We do not track liveness for reserved registers. It is unnecessary to
add them to block livein lists.

llvm-svn: 304059
2017-05-27 03:38:02 +00:00
Matthias Braun ac4307c41e LivePhysRegs: Rework constructor + documentation; NFC
- Take reference instead of pointer to a TRI that cannot be nullptr.
- Improve documentation comments.

llvm-svn: 304038
2017-05-26 21:51:00 +00:00
Francis Visoiu Mistrih b52e036600 BitVector: add iterators for set bits
Differential revision: https://reviews.llvm.org/D32060

llvm-svn: 303227
2017-05-17 01:07:53 +00:00
Krzysztof Parzyszek 44e25f37ae Move size and alignment information of regclass to TargetRegisterInfo
1. RegisterClass::getSize() is split into two functions:
   - TargetRegisterInfo::getRegSizeInBits(const TargetRegisterClass &RC) const;
   - TargetRegisterInfo::getSpillSize(const TargetRegisterClass &RC) const;
2. RegisterClass::getAlignment() is replaced by:
   - TargetRegisterInfo::getSpillAlignment(const TargetRegisterClass &RC) const;

This will allow making those values depend on subtarget features in the
future.

Differential Revision: https://reviews.llvm.org/D31783

llvm-svn: 301221
2017-04-24 18:55:33 +00:00
Matthias Braun d78597ec08 AArch64FrameLowering: Check if the ExtraCSSpill register is actually unused
The code assumed that when saving an additional CSR register
(ExtraCSSpill==true) we would have a free register throughout the
function. This was not true if this CSR register is also used to pass
values as in the swiftself case.

rdar://31451816

llvm-svn: 301057
2017-04-21 22:42:08 +00:00
Eric Christopher 60a245e0ff Reduce the number of times we query the subtarget for the same information.
llvm-svn: 299278
2017-03-31 23:12:27 +00:00
Reid Kleckner b518054b87 Rename AttributeSet to AttributeList
Summary:
This class is a list of AttributeSetNodes corresponding the function
prototype of a call or function declaration. This class used to be
called ParamAttrListPtr, then AttrListPtr, then AttributeSet. It is
typically accessed by parameter and return value index, so
"AttributeList" seems like a more intuitive name.

Rename AttributeSetImpl to AttributeListImpl to follow suit.

It's useful to rename this class so that we can rename AttributeSetNode
to AttributeSet later. AttributeSet is the set of attributes that apply
to a single function, argument, or return value.

Reviewers: sanjoy, javed.absar, chandlerc, pete

Reviewed By: pete

Subscribers: pete, jholewinski, arsenm, dschuff, mehdi_amini, jfb, nhaehnle, sbc100, void, llvm-commits

Differential Revision: https://reviews.llvm.org/D31102

llvm-svn: 298393
2017-03-21 16:57:19 +00:00
Eugene Zelenko 11f6907f40 [AArch64] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 292996
2017-01-25 00:29:26 +00:00
Diana Picus 116bbab4e4 [CodeGen] Rename MachineInstrBuilder::addOperand. NFC
Rename from addOperand to just add, to match the other method that has been
added to MachineInstrBuilder for adding more than just 1 operand.

See https://reviews.llvm.org/D28057 for the whole discussion.

Differential Revision: https://reviews.llvm.org/D28556

llvm-svn: 291891
2017-01-13 09:58:52 +00:00
Matthias Braun f23ef437cc Move FrameInstructions from MachineModuleInfo to MachineFunction
This is per function data so it is better kept at the function instead
of the module.

This is a necessary step to have machine module passes work properly.

Differential Revision: https://reviews.llvm.org/D27185

llvm-svn: 288291
2016-11-30 23:48:42 +00:00
Benjamin Kramer b7d3311c77 Move helpers into anonymous namespaces. NFC.
llvm-svn: 277916
2016-08-06 11:13:10 +00:00
Matthias Braun 941a705b7b MachineFunction: Return reference for getFrameInfo(); NFC
getFrameInfo() never returns nullptr so we should use a reference
instead of a pointer.

llvm-svn: 277017
2016-07-28 18:40:00 +00:00
Duncan P. N. Exon Smith ab53fd9b50 AArch64: Avoid implicit iterator conversions, NFC
Avoid implicit conversions from MachineInstrBundleInstr to MachineInstr*
in the AArch64 backend, mainly by preferring MachineInstr& over
MachineInstr* when a pointer isn't nullable.

llvm-svn: 274924
2016-07-08 20:29:42 +00:00
Matthias Braun 332bb5c236 AArch64: Replace a RegScavenger instance with LivePhysRegs
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
2016-07-06 21:31:27 +00:00
Benjamin Kramer bdc4956bac Pass DebugLoc and SDLoc by const ref.
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.

llvm-svn: 272512
2016-06-12 15:39:02 +00:00
Geoff Berry 66f6b65fed [PEI, AArch64] Use empty spaces in stack area for local stack slot allocation.
Summary:
If the target requests it, use emptry spaces in the fixed and
callee-save stack area to allocate local stack objects.

AArch64: Change last callee-save reg stack object alignment instead of
size to leave a gap to take advantage of above change.

Reviewers: t.p.northover, qcolombet, MatzeB

Subscribers: rengolin, mcrosier, llvm-commits, aemerson

Differential Revision: http://reviews.llvm.org/D20220

llvm-svn: 271527
2016-06-02 16:22:07 +00:00
Geoff Berry 74cb718ea9 [AArch64] Fix bug in large stack spill slot handling (PR27717)
Summary:
Fix bug in MachO path where a frame index offset would not be reserved
for handling large frames when an extra non-used callee-save register
was saved.  In the case where the extra register is reserved or not a
GPR (e.g. %FP in the MachO case), this would lead to the register
scavenger later failing when called from PrologEpilogInserter.

Reviewers: t.p.northover

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D20185

llvm-svn: 269697
2016-05-16 20:52:28 +00:00
Geoff Berry a5335647d5 [AArch64] Combine callee-save and local stack SP adjustment instructions.
Summary:
If a function needs to allocate both callee-save stack memory and local
stack memory, we currently decrement/increment the SP in two steps:
first for the callee-save area, and then for the local stack area.  This
changes the code to allocate them both at once at the very beginning/end
of the function.  This has two benefits:

1) there is one fewer sub/add micro-op in the prologue/epilogue

2) the stack adjustment instructions act as a scheduling barrier, so
moving them to the very beginning/end of the function increases post-RA
scheduler's ability to move instructions (that only depend on argument
registers) before any of the callee-save stores

This change can cause an increase in instructions if the original local
stack SP decrement could be folded into the first store to the stack.
This occurs when the first local stack store is to stack offset 0.  In
this case we are trading off one more sub instruction for one fewer sub
micro-op (along with benefits (2) and (3) above).

Reviewers: t.p.northover

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18619

llvm-svn: 268746
2016-05-06 16:34:59 +00:00
Geoff Berry c376406669 [AArch64] Add MMOs to callee-save load/store instructions.
Summary:
Without MMOs, the callee-save load/store instructions were treated as
volatile by the MI post-RA scheduler and AArch64LoadStoreOptimizer.

Reviewers: t.p.northover, mcrosier

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D17661

llvm-svn: 266439
2016-04-15 15:16:19 +00:00
Matthias Braun 74a0bd319a AArch64: Use a callee save registers for swiftself parameters
It is very likely that the swiftself parameter is alive throughout most
functions function so putting it into a callee save register should
avoid spills for the callers with only a minimum amount of extra spills
in the callees.

Currently the generated code is correct but unnecessarily spills and
reloads arguments passed in callee save registers, I will address this
in upcoming patches.

This also adds a missing check that for tail calls the preserved value
of the caller must be the same as the callees parameter.

Differential Revision: http://reviews.llvm.org/D19007

llvm-svn: 266251
2016-04-13 21:43:16 +00:00
Manman Ren 5751814eda Swift Calling Convention: swifterror target support.
Differential Revision: http://reviews.llvm.org/D18716

llvm-svn: 265997
2016-04-11 21:08:06 +00:00
Matthias Braun 8e594fdf19 AArch64: Fix compile error
Fixed to adapt a use of enterBasicBlock() in my last commit (because I
had follow on patches in my repository that change the code).

llvm-svn: 265513
2016-04-06 02:59:44 +00:00
Hans Wennborg e1a2e90ffa Change eliminateCallFramePseudoInstr() to return an iterator
This will become necessary in a subsequent change to make this method
merge adjacent stack adjustments, i.e. it might erase the previous
and/or next instruction.

It also greatly simplifies the calls to this function from Prolog-
EpilogInserter. Previously, that had a bunch of logic to resume iteration
after the call; now it just continues with the returned iterator.

Note that this changes the behaviour of PEI a little. Previously,
it attempted to re-visit the new instruction created by
eliminateCallFramePseudoInstr(). That code was added in r36625,
but I can't see any reason for it: the new instructions will obviously
not be pseudo instructions, they will not have FrameIndex operands,
and we have already accounted for the stack adjustment.

Differential Revision: http://reviews.llvm.org/D18627

llvm-svn: 265036
2016-03-31 18:33:38 +00:00
Chad Rosier 27c352d26d [AArch64] Refactor AArch64FrameLowering::emitPrologue. NFC.
http://reviews.llvm.org/D18125
Patch by Aditya Kumar.

llvm-svn: 263461
2016-03-14 18:24:34 +00:00
Chad Rosier 6d98655070 [AArch64] Break the dependency between FP and SP when possible.
When the SP in not changed because of realignment/VLAs etc., we restore the SP
by using the previous value of SP and not the FP. Breaking the dependency will
help in cases when the epilog of a callee is close to the epilog of the caller;
for then "sub sp, fp, #" depends on the load restoring the FP in the epilog of
the callee.

http://reviews.llvm.org/D18060
Patch by Aditya Kumar and Evandro Menezes.

llvm-svn: 263458
2016-03-14 18:17:41 +00:00
Roman Levenstein 2792b3f02f Add support for a preserve_most calling convention to the AArch64 backend.
This change adds a support for a preserve_most calling convention to the AArch64 backend, similar to how it was done for X86-64.

There is also a subsequent patch on top of this one to add a tail-calls support for this calling convention.

Differential Revision: http://reviews.llvm.org/D18016

llvm-svn: 263092
2016-03-10 04:35:09 +00:00
Geoff Berry 62c1a1e7c7 [AArch64] Enable non-leaf frame pointer elimination.
Summary:
This change enables frame pointer elimination in non-leaf functions.
The -fomit-frame-pointer option still needs to be used when compiling
via clang (or an equivalent method of not setting the
'no-frame-pointer-elim*' function attributes if generating llvm IR via
some other method) to take advantage of this optimization.

This change should be NFC when compiling via clang without
-fomit-frame-pointer.

Reviewers: t.p.northover

Subscribers: aemerson, rengolin, tberghammer, qcolombet, llvm-commits, danalbert, mcrosier, srhines

Differential Revision: http://reviews.llvm.org/D17730

llvm-svn: 262495
2016-03-02 17:58:31 +00:00
Eric Christopher 114fa1c3f6 Simplify some boolean conditional return statements in AArch64.
http://reviews.llvm.org/D9979

Patch by Richard Thomson (and some conflict resolution by me).

llvm-svn: 262266
2016-02-29 22:50:49 +00:00
Geoff Berry 62d472507e [AArch64] Clean up callee-save CFI emission. NFC.
Summary:
Avoid special case for FP, LR CFI emission and just allow general
AArch64FrameLowering::emitCalleeSavedFrameMoves() to handle them.  Also,
stop recalculating the stack offsets in emitCalleeSavedFrameMoves()
since we can just reuse the previously calculated offset stored in the
MachineFrameInfo.

Depends on D17000

Reviewers: t.p.northover, rengolin, mcrosier, jmolloy

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D17004

llvm-svn: 261885
2016-02-25 16:36:08 +00:00
Geoff Berry a1c6269c91 [AArch64] Fix fastcc -tailcallopt epilog code generation.
Summary:
Fix a bug in epilog generation where the incoming stack arguments were
not being popped for fastcc functions when -tailcallopt was passed.

Reviewers: t.p.northover, mcrosier, jmolloy, rengolin

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D16894

llvm-svn: 261650
2016-02-23 16:54:36 +00:00
Geoff Berry 7e4ba3dc02 [AArch64][ShrinkWrap] Fix bug in prolog clobbering live reg when shrink wrapping.
Summary: See bug https://llvm.org/bugs/show_bug.cgi?id=26642

Reviewers: qcolombet, t.p.northover

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D17350

llvm-svn: 261349
2016-02-19 18:27:32 +00:00
Geoff Berry c25d3bd238 [AArch64] Reduce number of callee-save save/restores.
Summary:
Before this change, callee-save registers would be rounded up to even
pairs of GPRs and FPRs.  This change eliminates these extra padding
load/stores, though it does keep the stack allocation the same size
unless both the GPR and FPR sets have an odd size, in which case one
full pair stack slot (16 bytes) is saved.

This optimization cannot currently be done for MachO targets since they
rely on a fast-path .debug_frame equivalent that can only encode
callee-save registers as pairs.

Reviewers: t.p.northover, rengolin, mcrosier, jmolloy

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D17000

llvm-svn: 260689
2016-02-12 16:31:41 +00:00
Geoff Berry 29d4a695f4 [AArch64] Simplify prolog/epilog callee save/restore. NFC.
Summary:
Factor out common code for callee-save register pair calculation.  This
is intended to simplify follow-on changes that reduce the number of
registers saved/restored.

Depends on D16732

Reviewers: mcrosier, jmolloy, t.p.northover

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D16734

llvm-svn: 259384
2016-02-01 19:07:06 +00:00
Geoff Berry 04bf91a8c1 [AArch64] Simplify callee-save register save/restore. NFC.
Summary:
Simplify callee-save register save/restore code generation by
remembering the size of the callee-save area when it is computed so we
don't have to scan the prologue/epilogue instructions again later to
reconstruct it.

This is intended to simplify follow-on changes that reduce the number of
registers saved/restored.

Reviewers: mcrosier, jmolloy, t.p.northover

Subscribers: aemerson, rengolin, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D16732

llvm-svn: 259365
2016-02-01 16:29:19 +00:00
Chad Rosier 401a4ab8d8 Typo.
llvm-svn: 258137
2016-01-19 16:50:45 +00:00
Rui Ueyama da00f2fdf4 Update to use new name alignTo().
llvm-svn: 257804
2016-01-14 21:06:47 +00:00
Matthias Braun 454192917b AArch64: Simplify emitEpilogue() and related code; NFC
This is in preparation to an upcoming patch.

llvm-svn: 255872
2015-12-17 03:18:47 +00:00
Ahmed Bougacha 66834ec6e1 [AArch64] Simplify some TRI/TII getters. NFC.
We don't need static_casts when we use the right Subtarget.

llvm-svn: 255836
2015-12-16 22:54:06 +00:00
Tim Northover 775aaeb765 Remove windows line endings introduced by r252177. NFC.
llvm-svn: 252217
2015-11-05 21:54:58 +00:00
Oleg Ranevskyy 057c5a6b2b [DebugInfo] Fix ARM/AArch64 prologue_end position. Related to D11268.
Summary:
This review is related to another review request http://reviews.llvm.org/D11268, does the same and merely fixes a couple of issues with it.

D11268 is quite old and has merge conflicts against the current trunk.
This request 
 - rebases D11268 onto the new trunk;
 - resolves the merge conflicts;
 - fixes the prologue_end tests, which do not pass due to the subprogram definitions not marked as distinct.

Reviewers: echristo, rengolin, kubabrecka

Subscribers: aemerson, rengolin, jyknight, dsanders, llvm-commits, asl

Differential Revision: http://reviews.llvm.org/D14338

llvm-svn: 252177
2015-11-05 17:50:17 +00:00
James Y Knight 5567bafe93 Remove redundant TargetFrameLowering::getFrameIndexOffset virtual
function.

This was the same as getFrameIndexReference, but without the FrameReg
output.

Differential Revision: http://reviews.llvm.org/D12042

llvm-svn: 245148
2015-08-15 02:32:35 +00:00
Benjamin Kramer df005cbe19 Fix some comment typos.
llvm-svn: 244402
2015-08-08 18:27:36 +00:00
Mehdi Amini bd7287ebe5 Move most user of TargetMachine::getDataLayout to the Module one
Summary:
This change is part of a series of commits dedicated to have a single
DataLayout during compilation by using always the one owned by the
module.

This patch is quite boring overall, except for some uglyness in
ASMPrinter which has a getDataLayout function but has some clients
that use it without a Module (llmv-dsymutil, llvm-dwarfdump), so
some methods are taking a DataLayout as parameter.

Reviewers: echristo

Subscribers: yaron.keren, rafael, llvm-commits, jholewinski

Differential Revision: http://reviews.llvm.org/D11090

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 242386
2015-07-16 06:11:10 +00:00
JF Bastien c8f48c19d3 WebAssembly: fix build breakage.
Summary:
processFunctionBeforeCalleeSavedScan was renamed to determineCalleeSaves and now takes a BitVector parameter as of rL242165, reviewed in http://reviews.llvm.org/D10909

WebAssembly is still marked as experimental and therefore doesn't build by default. It does, however, grep by default! I notice that processFunctionBeforeCalleeSavedScan is still mentioned in a few comments and error messages, which I also fixed.

Reviewers: qcolombet, sunfish

Subscribers: jfb, dsanders, hfinkel, MatzeB, llvm-commits

Differential Revision: http://reviews.llvm.org/D11199

llvm-svn: 242242
2015-07-14 23:06:07 +00:00
Matthias Braun 9912bb817c MachineRegisterInfo: Remove UsedPhysReg infrastructure
We have a detailed def/use lists for every physical register in
MachineRegisterInfo anyway, so there is little use in maintaining an
additional bitset of which ones are used.

Removing it frees us from extra book keeping. This simplifies
VirtRegMap.

Differential Revision: http://reviews.llvm.org/D10911

llvm-svn: 242173
2015-07-14 17:52:07 +00:00
Matthias Braun 0256486532 PrologEpilogInserter: Rewrite API to determine callee save regsiters.
This changes TargetFrameLowering::processFunctionBeforeCalleeSavedScan():

- Rename the function to determineCalleeSaves()
- Pass a bitset of callee saved registers by reference, thus avoiding
  the function-global PhysRegUsed bitset in MachineRegisterInfo.
- Without PhysRegUsed the implementation is fine tuned to not save
  physcial registers which are only read but never modified.

Related to rdar://21539507

Differential Revision: http://reviews.llvm.org/D10909

llvm-svn: 242165
2015-07-14 17:17:13 +00:00
Evgeniy Stepanov 00b3020453 Fix AArch64 prologue for empty frame with dynamic allocas.
Fixes PR23804: assertion failure in emitPrologue in the case of a
function with an empty frame and a dynamic alloca that needs stack
realignment. This is a typical case for AddressSanitizer.

llvm-svn: 241943
2015-07-10 21:24:07 +00:00
Matthias Braun fa3872e7ad MachineInstr: Change return value of getOpcode() to unsigned.
This was previously returning int. However there are no negative opcode
numbers and more importantly this was needlessly different from
MCInstrDesc::getOpcode() (which even is the value returned here) and
SDValue::getOpcode()/SDNode::getOpcode().

llvm-svn: 237611
2015-05-18 20:27:55 +00:00
Jim Grosbach 6f482000e9 MC: Clean up method names in MCContext.
The naming was a mish-mash of old and new style. Update to be consistent
with the new. NFC.

llvm-svn: 237594
2015-05-18 18:43:14 +00:00
Quentin Colombet 61b305edfd [ShrinkWrap] Add (a simplified version) of shrink-wrapping.
This patch introduces a new pass that computes the safe point to insert the
prologue and epilogue of the function.
The interest is to find safe points that are cheaper than the entry and exits
blocks.

As an example and to avoid regressions to be introduce, this patch also
implements the required bits to enable the shrink-wrapping pass for AArch64.


** Context **

Currently we insert the prologue and epilogue of the method/function in the
entry and exits blocks. Although this is correct, we can do a better job when
those are not immediately required and insert them at less frequently executed
places.
The job of the shrink-wrapping pass is to identify such places.


** Motivating example **

Let us consider the following function that perform a call only in one branch of
a if:
define i32 @f(i32 %a, i32 %b)  {
 %tmp = alloca i32, align 4
 %tmp2 = icmp slt i32 %a, %b
 br i1 %tmp2, label %true, label %false

true:
 store i32 %a, i32* %tmp, align 4
 %tmp4 = call i32 @doSomething(i32 0, i32* %tmp)
 br label %false

false:
 %tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %0 ]
 ret i32 %tmp.0
}

On AArch64 this code generates (removing the cfi directives to ease
readabilities):
_f:                                     ; @f
; BB#0:
  stp x29, x30, [sp, #-16]!
  mov  x29, sp
  sub sp, sp, #16             ; =16
  cmp  w0, w1
  b.ge  LBB0_2
; BB#1:                                 ; %true
  stur  w0, [x29, #-4]
  sub x1, x29, #4             ; =4
  mov  w0, wzr
  bl  _doSomething
LBB0_2:                                 ; %false
  mov  sp, x29
  ldp x29, x30, [sp], #16
  ret

With shrink-wrapping we could generate:
_f:                                     ; @f
; BB#0:
  cmp  w0, w1
  b.ge  LBB0_2
; BB#1:                                 ; %true
  stp x29, x30, [sp, #-16]!
  mov  x29, sp
  sub sp, sp, #16             ; =16
  stur  w0, [x29, #-4]
  sub x1, x29, #4             ; =4
  mov  w0, wzr
  bl  _doSomething
  add sp, x29, #16            ; =16
  ldp x29, x30, [sp], #16
LBB0_2:                                 ; %false
  ret

Therefore, we would pay the overhead of setting up/destroying the frame only if
we actually do the call.


** Proposed Solution **

This patch introduces a new machine pass that perform the shrink-wrapping
analysis (See the comments at the beginning of ShrinkWrap.cpp for more details).
It then stores the safe save and restore point into the MachineFrameInfo
attached to the MachineFunction.
This information is then used by the PrologEpilogInserter (PEI) to place the
related code at the right place. This pass runs right before the PEI.

Unlike the original paper of Chow from PLDI’88, this implementation of
shrink-wrapping does not use expensive data-flow analysis and does not need hack
to properly avoid frequently executed point. Instead, it relies on dominance and
loop properties.

The pass is off by default and each target can opt-in by setting the
EnableShrinkWrap boolean to true in their derived class of TargetPassConfig.
This setting can also be overwritten on the command line by using
-enable-shrink-wrap.

Before you try out the pass for your target, make sure you properly fix your
emitProlog/emitEpilog/adjustForXXX method to cope with basic blocks that are not
necessarily the entry block.


** Design Decisions **

1. ShrinkWrap is its own pass right now. It could frankly be merged into PEI but
for debugging and clarity I thought it was best to have its own file.
2. Right now, we only support one save point and one restore point. At some
point we can expand this to several save point and restore point, the impacted
component would then be:
- The pass itself: New algorithm needed.
- MachineFrameInfo: Hold a list or set of Save/Restore point instead of one
  pointer.
- PEI: Should loop over the save point and restore point.
Anyhow, at least for this first iteration, I do not believe this is interesting
to support the complex cases. We should revisit that when we motivating
examples.

Differential Revision: http://reviews.llvm.org/D9210

<rdar://problem/3201744>

llvm-svn: 236507
2015-05-05 17:38:16 +00:00
Manman Ren 0e20822887 [AArch64] Refactor out codes that depend on specific CS save sequence.
No functionality change.

llvm-svn: 236143
2015-04-29 20:03:38 +00:00
Quentin Colombet fd7475b5e8 [AArch64] Strengthen the code for the prologue insertion.
The spilled registers are pristine and thus, correctly handled by
the register scavenger and so on, but the liveness information is
strictly speaking wrong at this point.
Fix that.

llvm-svn: 234664
2015-04-10 23:14:34 +00:00
Kristof Beyls 17cb8982f4 [AArch64] Add support for dynamic stack alignment
Differential Revision: http://reviews.llvm.org/D8876

llvm-svn: 234471
2015-04-09 08:49:47 +00:00
Duncan P. N. Exon Smith 003bb7d96e AArch64: Canonicalize access to function attributes, NFC
Canonicalize access to function attributes to use the simpler API.

getAttributes().getAttribute(AttributeSet::FunctionIndex, Kind)
  => getFnAttribute(Kind)

getAttributes().hasAttribute(AttributeSet::FunctionIndex, Kind)
  => hasFnAttribute(Kind)

llvm-svn: 229218
2015-02-14 02:09:06 +00:00
Eric Christopher 8b7706517c Move DataLayout back to the TargetMachine from TargetSubtargetInfo
derived classes.

Since global data alignment, layout, and mangling is often based on the
DataLayout, move it to the TargetMachine. This ensures that global
data is going to be layed out and mangled consistently if the subtarget
changes on a per function basis. Prior to this all targets(*) have
had subtarget dependent code moved out and onto the TargetMachine.

*One target hasn't been migrated as part of this change: R600. The
R600 port has, as a subtarget feature, the size of pointers and
this affects global data layout. I've currently hacked in a FIXME
to enable progress, but the port needs to be updated to either pass
the 64-bitness to the TargetMachine, or fix the DataLayout to
avoid subtarget dependent features.

llvm-svn: 227113
2015-01-26 19:03:15 +00:00
Greg Fitzgerald fa78d08675 [AArch64] Implement GHC calling convention
Original patch by Luke Iannini.  Minor improvements and test added by
Erik de Castro Lopo.

Differential Revision: http://reviews.llvm.org/D6877

From: Erik de Castro Lopo <erikd@mega-nerd.com>
llvm-svn: 226473
2015-01-19 17:40:05 +00:00
Adrian Prantl b9fa945d51 ARM/AArch64: Attach the FrameSetup MIFlag to CFI instructions.
Debug info marks the first instruction without the FrameSetup flag
as being the end of the function prologue. Any CFI instructions in the
middle of the function prologue would cause debug info to end the prologue
too early and worse, attach the line number of the CFI instruction, which
incidentally is often 0.

llvm-svn: 224294
2014-12-16 00:20:49 +00:00
Juergen Ributzka 99bd3cba8b [Stackmaps] Make ithe frame-pointer required for stackmaps.
Do not eliminate the frame pointer if there is a stackmap or patchpoint in the
function. All stackmap references should be FP relative.

This fixes PR21107.

llvm-svn: 218920
2014-10-02 22:21:49 +00:00
Sylvestre Ledru 469de19a09 Fix typos:
* libaries => libraries
* avaiable => available

llvm-svn: 215366
2014-08-11 18:04:46 +00:00
Eric Christopher fc6de428c8 Have MachineFunction cache a pointer to the subtarget to make lookups
shorter/easier and have the DAG use that to do the same lookup. This
can be used in the future for TargetMachine based caching lookups from
the MachineFunction easily.

Update the MIPS subtarget switching machinery to update this pointer
at the same time it runs.

llvm-svn: 214838
2014-08-05 02:39:49 +00:00
Eric Christopher d913448b38 Remove the TargetMachine forwards for TargetSubtargetInfo based
information and update all callers. No functional change.

llvm-svn: 214781
2014-08-04 21:25:23 +00:00
Benjamin Kramer 1f8930e3d3 Run sort_includes.py on the AArch64 backend.
No functionality change.

llvm-svn: 213938
2014-07-25 11:42:14 +00:00
Eric Christopher bc76b97797 Remove the uses of AArch64TargetMachine and AArch64Subtarget from
AArch64FrameLowering.

llvm-svn: 210548
2014-06-10 17:33:39 +00:00
Tim Northover 3b0846e8f7 AArch64/ARM64: move ARM64 into AArch64's place
This commit starts with a "git mv ARM64 AArch64" and continues out
from there, renaming the C++ classes, intrinsics, and other
target-local objects for consistency.

"ARM64" test directories are also moved, and tests that began their
life in ARM64 use an arm64 triple, those from AArch64 use an aarch64
triple. Both should be equivalent though.

This finishes the AArch64 merge, and everyone should feel free to
continue committing as normal now.

llvm-svn: 209577
2014-05-24 12:50:23 +00:00
Tim Northover cc08e1fe1b AArch64/ARM64: remove AArch64 from tree prior to renaming ARM64.
I'm doing this in two phases for a better "git blame" record. This
commit removes the previous AArch64 backend and redirects all
functionality to ARM64. It also deduplicates test-lines and removes
orphaned AArch64 tests.

The next step will be "git mv ARM64 AArch64" and rewire most of the
tests.

Hopefully LLVM is still functional, though it would be even better if
no-one ever had to care because the rename happens straight
afterwards.

llvm-svn: 209576
2014-05-24 12:42:26 +00:00
Craig Topper 840beec2d0 Make consistent use of MCPhysReg instead of uint16_t throughout the tree.
llvm-svn: 205610
2014-04-04 05:16:06 +00:00
Rafael Espindola b1f25f1b93 Replace PROLOG_LABEL with a new CFI_INSTRUCTION.
The old system was fairly convoluted:
* A temporary label was created.
* A single PROLOG_LABEL was created with it.
* A few MCCFIInstructions were created with the same label.

The semantics were that the cfi instructions were mapped to the PROLOG_LABEL
via the temporary label. The output position was that of the PROLOG_LABEL.
The temporary label itself was used only for doing the mapping.

The new CFI_INSTRUCTION has a 1:1 mapping to MCCFIInstructions and points to
one by holding an index into the CFI instructions of this function.

I did consider removing MMI.getFrameInstructions completelly and having
CFI_INSTRUCTION own a MCCFIInstruction, but MCCFIInstructions have non
trivial constructors and destructors and are somewhat big, so the this setup
is probably better.

The net result is that we don't create temporary labels that are never used.

llvm-svn: 203204
2014-03-07 06:08:31 +00:00
Benjamin Kramer b6d0bd48bd [C++11] Replace llvm::next and llvm::prior with std::next and std::prev.
Remove the old functions.

llvm-svn: 202636
2014-03-02 12:27:27 +00:00
Chandler Carruth 8a8cd2bab9 Re-sort all of the includes with ./utils/sort_includes.py so that
subsequent changes are easier to review. About to fix some layering
issues, and wanted to separate out the necessary churn.

Also comment and sink the include of "Windows.h" in three .inc files to
match the usage in Memory.inc.

llvm-svn: 198685
2014-01-07 11:48:04 +00:00
Craig Topper de1f151115 Add const qualifier to some static arrays.
llvm-svn: 186309
2013-07-15 07:02:45 +00:00
Bill Wendling bc07a8900c Use pointers to the MCAsmInfo and MCRegInfo.
Someone may want to do something crazy, like replace these objects if they
change or something.

No functionality change intended.

llvm-svn: 184175
2013-06-18 07:20:20 +00:00
Rafael Espindola b08d2c2db0 Remove addFrameMove.
Now that we have good testing, remove addFrameMove and create cfi
instructions directly.

llvm-svn: 182052
2013-05-16 21:02:15 +00:00
Rafael Espindola 1b09836bc3 Change getFrameMoves to return a const reference.
To add a frame now there is a dedicated addFrameMove which also takes
care of constructing the move itself.

llvm-svn: 181657
2013-05-11 02:38:11 +00:00
Tim Northover 2ac2d4c59d AArch64: remove unnecessary check that RS is valid
AArch64 always demands a register-scavenger, so the pointer should never be
NULL. However, in the spirit of paranoia, we'll assert it before use just in
case.

llvm-svn: 180080
2013-04-23 06:55:15 +00:00
Hal Finkel 9e331c2f9c Allow the register scavenger to spill multiple registers
This patch lets the register scavenger make use of multiple spill slots in
order to guarantee that it will be able to provide multiple registers
simultaneously.

To support this, the RS's API has changed slightly: setScavengingFrameIndex /
getScavengingFrameIndex have been replaced by addScavengingFrameIndex /
isScavengingFrameIndex / getScavengingFrameIndices.

In forthcoming commits, the PowerPC backend will use this capability in order
to implement the spilling of condition registers, and some special-purpose
registers, without relying on r0 being reserved. In some cases, spilling these
registers requires two GPRs: one for addressing and one to hold the value being
transferred.

llvm-svn: 177774
2013-03-22 23:32:27 +00:00