This prevents the emission of DAG-generated vreg definitions after a
tail call be dropping them entirely (on the grounds that nothing could
use them anyway, and they interfere with O0 CodeGen).
llvm-svn: 185754
A "pkhtb x, x, y asr #num" uses the lower 16 bits of "y asr #num" and packs them
in the bottom half of "x". An arithmetic and logic shift are only equivalent in
this context if the shift amount is 16. We would be shifting in ones into the
bottom 16bits instead of zeros if "y" is negative.
radar://14338767
llvm-svn: 185712
In the SelectionDAG immediate operands to inline asm are constructed as
two separate operands. The first is a constant of value InlineAsm::Kind_Imm
and the second is a constant with the value of the immediate.
In ARMDAGToDAGISel::SelectInlineAsm, if we reach an operand of Kind_Imm we
should skip over the next operand too.
llvm-svn: 185688
In the ARM back-end, build_vector nodes are lowered to a target specific
build_vector that uses floating point type.
This works well, unless the inserted bitcasts survive until instruction
selection. In that case, they incur moves between integer unit and floating
point unit that may result in inefficient code.
In other words, this conversion may introduce artificial dependencies when the
code leading to the build vector cannot be completed with a floating point type.
In particular, this happens when loads are not aligned.
Before this patch, in that case, the compiler generates general purpose loads
and creates the floating point vector from them, instead of directly using the
vector unit.
The patch uses a vector friendly sequence of code when the inserted bitcasts to
floating point survived DAGCombine.
This is done by a target specific DAGCombine that changes the target specific
build_vector into a sequence of insert_vector_elt that get rid of the bitcasts.
<rdar://problem/14170854>
llvm-svn: 185587
Swift cores implement store barriers that are stronger than the ARM
specification but weaker than general barriers. They are, in fact, just about
enough to provide the ordering needed for atomic operations with release
semantics.
This patch makes use of that quirk.
llvm-svn: 185527
Turns out I'd misread the architecture reference manual and thought
that was a load/store-store barrier, when it's not.
Thanks for pointing it out Eli!
llvm-svn: 185356
I believe the full "dmb ish" barrier is not required to guarantee release
semantics for atomic operations. The weaker "dmb ishst" prevents previous
operations being reordered with a store executed afterwards, which is enough.
A key point to note (fortunately already correct) is that this barrier alone is
*insufficient* for sequential consistency, no matter how liberally placed.
llvm-svn: 185339
should expand ATOMIC_CMP_SWAP nodes the same way that it does for ATOMIC_SWAP.
Since ATOMIC_LOADs on some targets (e.g. older ARM variants) get legalized to
ATOMIC_CMP_SWAPs, the missing case had been causing i64 atomic loads to crash
during isel.
<rdar://problem/14074644>
llvm-svn: 185186
This patch assigns paired GPRs for inline asm with
64-bit data on ARM. It's enabled for both ARM and Thumb to support modifiers
like %H, %Q, %R.
llvm-svn: 185169
We were generating intrinsics for NEON fixed-point conversions that didn't
exist (e.g. float -> i16). There are two cases to consider:
+ iN is smaller than float. In this case we can do the conversion but need an
extend or truncate as well.
+ iN is larger than float. In this case using the NEON conversion would be
incorrect so we don't perform any combining.
llvm-svn: 185158
No functionality change.
It should suffice to check the type of a debug info metadata, instead of
calling Verify. For cases where we know the type of a DI metadata, use
assert.
Also update testing cases to make them conform to the format of DI classes.
llvm-svn: 185135
A FastISel optimization was causing us to emit no information for such
parameters & when they go missing we end up emitting a different
function type. By avoiding that shortcut we not only get types correct
(very important) but also location information (handy) - even if it's
only live at the start of a function & may be clobbered later.
Reviewed/discussion by Evan Cheng & Dan Gohman.
llvm-svn: 184604
it at the moment.
This allows to form more paired loads even when stack coloring pass destroys the
memoryoperand's value.
<rdar://problem/13978317>
llvm-svn: 184492
value is zero.
This allows optmizations to kick in more easily.
Fix some test cases so that they remain meaningful (i.e., not completely dead
coded) when optimizations apply.
<rdar://problem/14096009> superfluous multiply by high part of zero-extended
value.
llvm-svn: 184222
The main advantages here are way better heuristics, taking into account not
just loop depth but also __builtin_expect and other static heuristics and will
eventually learn how to use profile info. Most of the work in this patch is
pushing the MachineBlockFrequencyInfo analysis into the right places.
This is good for a 5% speedup on zlib's deflate (x86_64), there were some very
unfortunate spilling decisions in its hottest loop in longest_match(). Other
benchmarks I tried were mostly neutral.
This changes register allocation in subtle ways, update the tests for it.
2012-02-20-MachineCPBug.ll was deleted as it's very fragile and the instruction
it looked for was gone already (but the FileCheck pattern picked up unrelated
stuff).
llvm-svn: 184105
Rather than using the full power of target-specific addressing modes in
DBG_VALUEs with Frame Indicies, simply use Frame Index + Offset. This
reduces the complexity of debug info handling down to two
representations of values (reg+offset and frame index+offset) rather
than three or four.
Ideally we could ensure that frame indicies had been eliminated by the
time we reached an assembly or dwarf generation, but I haven't spent the
time to figure out where the FIs are leaking through into that & whether
there's a good place to convert them. Some FI+offset=>reg+offset
conversion is done (see PrologEpilogInserter, for example) which is
necessary for some SelectionDAG assumptions about registers, I believe,
but it might be possible to make this a more thorough conversion &
ensure there are no remaining FIs no matter how instruction selection
is performed.
llvm-svn: 184066
in functions which call __builtin_unwind_init()
__builtin_unwind_init() is an undocumented gcc intrinsic which has this effect,
and is used in libgcc_eh.
Goes part of the way toward fixing PR8541.
llvm-svn: 183984
This is a resubmit of r182877, which was reverted because it broken
MCJIT tests on ARM. The patch leaves MCJIT on ARM as it was before: only
enabled for iOS. I've CC'ed people from the original review and revert.
FastISel was only enabled for iOS ARM and Thumb2, this patch enables it
for ARM (not Thumb2) on Linux and NaCl, but not MCJIT.
Thumb2 support needs a bit more work, mainly around register class
restrictions.
The patch punts to SelectionDAG when doing TLS relocation on non-Darwin
targets. I will fix this and other FastISel-to-SelectionDAG failures in
a separate patch.
The patch also forces FastISel to retain frame pointers: iOS always
keeps them for backtracking (so emitted code won't change because of
this), but Linux was getting much worse code that was incorrect when
using big frames (such as test-suite's lencod). I'll also fix this in a
later patch, it will probably require a peephole so that FastISel
doesn't rematerialize frame pointers back-to-back.
The test changes are straightforward, similar to:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20130513/174279.html
They also add a vararg test that got dropped in that change.
I ran all of lnt test-suite on A15 hardware with --optimize-option=-O0
and all the tests pass. All the tests also pass on x86 make check-all. I
also re-ran the check-all tests that failed on ARM, and they all seem to
pass.
llvm-svn: 183966
Since we have ARM unwind directive parser and assembler, we
can check the correctness in two stages:
1. From LLVM assembly (.ll) to ARM assembly (.s)
2. From ARM assembly (.s) to ELF object file (.o)
We already have several "*.s to *.o" test cases. This CL adds
some "*.ll to *.s" test cases and removes the redundant "*.ll to *.o"
test cases.
New test cases to check "*.ll to *.s" code generator:
- ehabi.ll: Check the correctness of the generated unwind directives.
- section-name.ll: Check the section name of functions.
Removed test cases:
- ehabi-mc-cantunwind.ll
(Covered by ehabi-cantunwind.ll, and eh-directive-cantunwind.s)
- ehabi-mc-compact-pr0.ll
(Covered by ehabi.ll, eh-compact-pr0.s, eh-directive-save.s, and
eh-directive-setfp.s)
- ehabi-mc-compact-pr1.ll
(Covered by ehabi.ll, eh-compact-pr1.s, eh-directive-save.s, and
eh-directive-setfp.s)
- ehabi-mc.ll
(Covered by ehabi.ll, and eh-directive-integrated-test.s)
- ehabi-mc-section-group.ll
(Covered by section-name.ll, and eh-directive-section-comdat.s)
- ehabi-mc-section.ll
(Covered by section-name.ll, and eh-directive-section.s)
- ehabi-mc-sh_link.ll
(Covered by eh-directive-text-section.s, and eh-directive-section.s)
llvm-svn: 183628
Changes to ARM unwind opcode assembler:
* Fix multiple .save or .vsave directives. Besides, the
order is preserved now.
* For the directives which will generate multiple opcodes,
such as ".save {r0-r11}", the order of the unwind opcode
is fixed now, i.e. the registers with less encoding value
are popped first.
* Fix the $sp offset calculation. Now, we can use the
.setfp, .pad, .save, and .vsave directives at any order.
Changes to test cases:
* Add test cases to check the order of multiple opcodes
for the .save directive.
* Fix the incorrect $sp offset in the test case. The
stack pointer offset specified in the test case was
incorrect. (Changed test cases: ehabi-mc-section.ll and
ehabi-mc.ll)
* The opcode to restore $sp are slightly reordered. The
behavior are not changed, and the new output is same
as the output of GNU as. (Changed test cases:
eh-directive-pad.s and eh-directive-setfp.s)
llvm-svn: 183627
instantiation issue with non-standard type.
Add a backend option to warn on a given stack size limit.
Option: -mllvm -warn-stack-size=<limit>
Output (if limit is exceeded):
warning: Stack size limit exceeded (<actual size>) in <functionName>.
The longer term plan is to hook that to a clang warning.
PR:4072
<rdar://problem/13987214>.
llvm-svn: 183595
Option: -mllvm -warn-stack-size=<limit>
Output (if limit is exceeded):
warning: Stack size limit exceeded (<actual size>) in <functionName>.
The longer term plan is to hook that to a clang warning.
PR:4072
<rdar://problem/13987214>
llvm-svn: 183552
My recent ARM FastISel patch exposed this bug:
http://llvm.org/bugs/show_bug.cgi?id=16178
The root cause is that it can't select integer sext/zext pre-ARMv6 and
asserts out.
The current integer sext/zext code doesn't handle other cases gracefully
either, so this patch makes it handle all sext and zext from i1/i8/i16
to i8/i16/i32, with and without ARMv6, both in Thumb and ARM mode. This
should fix the bug as well as make FastISel faster because it bails to
SelectionDAG less often. See fastisel-ext.patch for this.
fastisel-ext-tests.patch changes current tests to always use reg-imm AND
for 8-bit zext instead of UXTB. This simplifies code since it is
supported on ARMv4t and later, and at least on A15 both should perform
exactly the same (both have exec 1 uop 1, type I).
2013-05-31-char-shift-crash.ll is a bitcode version of the above bug
16178 repro.
fast-isel-ext.ll tests all sext/zext combinations that ARM FastISel
should now handle.
Note that my ARM FastISel enabling patch was reverted due to a separate
failure when dealing with MCJIT, I'll fix this second failure and then
turn FastISel on again for non-iOS ARM targets.
I've tested "make check-all" on my x86 box, and "lnt test-suite" on A15
hardware.
llvm-svn: 183551
Fix an assertion when the compiler encounters big constants whose bit width is
not a multiple of 64-bits.
Although clang would never generate something like this, the backend should be
able to handle any legal IR.
<rdar://problem/13363576>
llvm-svn: 183544
The ARM backend did not expect LDRBi12 to hold a constant pool operand.
Allow for LLVM to deal with the instruction similar to how it deals with
LDRi12.
This fixes PR16215.
llvm-svn: 183238
For COFF and MachO, sections semantically have relocations that apply to them.
That is not the case on ELF.
In relocatable objects (.o), a section with relocations in ELF has offsets to
another section where the relocations should be applied.
In dynamic objects and executables, relocations don't have an offset, they have
a virtual address. The section sh_info may or may not point to another section,
but that is not actually used for resolving the relocations.
This patch exposes that in the ObjectFile API. It has the following advantages:
* Most (all?) clients can handle this more efficiently. They will normally walk
all relocations, so doing an effort to iterate in a particular order doesn't
save time.
* llvm-readobj now prints relocations in the same way the native readelf does.
* probably most important, relocations that don't point to any section are now
visible. This is the case of relocations in the rela.dyn section. See the
updated relocation-executable.test for example.
llvm-svn: 182908
Fixes PR16146: gdb.base__call-ar-st.exp fails after
pre-RA-sched=source fixes.
Patch by Xiaoyi Guo!
This also fixes an unsupported dbg.value test case. Codegen was
previously incorrect but the test was passing by luck.
llvm-svn: 182885
FastISel was only enabled for iOS ARM and Thumb2, this patch enables it
for ARM (not Thumb2) on Linux and NaCl.
Thumb2 support needs a bit more work, mainly around register class
restrictions.
The patch punts to SelectionDAG when doing TLS relocation on non-Darwin
targets. I will fix this and other FastISel-to-SelectionDAG failures in
a separate patch.
The patch also forces FastISel to retain frame pointers: iOS always
keeps them for backtracking (so emitted code won't change because of
this), but Linux was getting much worse code that was incorrect when
using big frames (such as test-suite's lencod). I'll also fix this in a
later patch, it will probably require a peephole so that FastISel
doesn't rematerialize frame pointers back-to-back.
The test changes are straightforward, similar to:
http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20130513/174279.html
They also add a vararg test that got dropped in that change.
I ran all of test-suite on A15 hardware with --optimize-option=-O0 and
all the tests pass.
llvm-svn: 182877
This implements the @llvm.readcyclecounter intrinsic as the specific
MRC instruction specified in the ARM manuals for CPUs with the Power
Management extensions.
Older CPUs had slightly different methods which may also have to be
implemented eventually, but this should cover all v7 cases.
rdar://problem/13939186
llvm-svn: 182603
Now that the LiveDebugVariables pass is running *after* register
coalescing, the ConnectedVNInfoEqClasses class needs to deal with
DBG_VALUE instructions.
This only comes up when rematerialization during coalescing causes the
remaining live range of a virtual register to separate into two
connected components.
llvm-svn: 182592
Introduction:
In case when stack alignment is 8 and GPRs parameter part size is not N*8:
we add padding to GPRs part, so part's last byte must be recovered at
address K*8-1.
We need to do it, since remained (stack) part of parameter starts from
address K*8, and we need to "attach" "GPRs head" without gaps to it:
Stack:
|---- 8 bytes block ----| |---- 8 bytes block ----| |---- 8 bytes...
[ [padding] [GPRs head] ] [ ------ Tail passed via stack ------ ...
FIX:
Note, once we added padding we need to correct *all* Arg offsets that are going
after padded one. That's why we need this fix: Arg offsets were never corrected
before this patch. See new test-cases included in patch.
We also don't need to insert padding for byval parameters that are stored in GPRs
only. We need pad only last byval parameter and only in case it outsides GPRs
and stack alignment = 8.
Though, stack area, allocated for recovered byval params, must satisfy
"Size mod 8 = 0" restriction.
This patch reduces stack usage for some cases:
We can reduce ArgRegsSaveArea since inner N*4 bytes sized byval params my be
"packed" with alignment 4 in some cases.
llvm-svn: 182237
This patch matches GCC behavior: the code used to only allow unaligned
load/store on ARM for v6+ Darwin, it will now allow unaligned load/store
for v6+ Darwin as well as for v7+ on Linux and NaCl.
The distinction is made because v6 doesn't guarantee support (but LLVM
assumes that Apple controls hardware+kernel and therefore have
conformant v6 CPUs), whereas v7 does provide this guarantee (and
Linux/NaCl behave sanely).
The patch keeps the -arm-strict-align command line option, and adds
-arm-no-strict-align. They behave similarly to GCC's -mstrict-align and
-mnostrict-align.
I originally encountered this discrepancy in FastIsel tests which expect
unaligned load/store generation. Overall this should slightly improve
performance in most cases because of reduced I$ pressure.
llvm-svn: 182175
The transformation happening here is that we want to turn a
"mul(ext(X), ext(X))" into a "vmull(X, X)", stripping off the extension. We have
to make sure that X still has a valid vector type - possibly recreate an
extension to a smaller type. In case of a extload of a memory type smaller than
64 bit we used create a ext(load()). The problem with doing this - instead of
recreating an extload - is that an illegal type is exposed.
This patch fixes this by creating extloads instead of ext(load()) sequences.
Fixes PR15970.
radar://13871383
llvm-svn: 181842
ARM FastISel is currently only enabled for iOS non-Thumb1, and I'm working on
enabling it for other targets. As a first step I've fixed some of the tests.
Changes to ARM FastISel tests:
- Different triples don't generate the same relocations (especially
movw/movt versus constant pool loads). Use a regex to allow either.
- Mangling is different. Use a regex to allow either.
- The reserved registers are sometimes different, so registers get
allocated in a different order. Capture the names only where this
occurs.
- Add -verify-machineinstrs to some tests where it works. It doesn't
work everywhere it should yet.
- Add -fast-isel-abort to many tests that didn't have it before.
- Split out the VarArg test from fast-isel-call.ll into its own
test. This simplifies test setup because of --check-prefix.
Patch by JF Bastien
llvm-svn: 181801
return values are bitcasts.
The chain had previously been being clobbered with the entry node to
the dag, which sometimes caused other code in the function to be
erroneously deleted when tailcall optimization kicked in.
<rdar://problem/13827621>
llvm-svn: 181696
