indirect branch at the end of the BB. Otherwise if-converter, branch folding
pass may incorrectly update its successor info if it consider BB as fallthrough
to the next BB.
rdar://13782395
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181161 91177308-0d34-0410-b5e6-96231b3b80d8
at all of the operands. Previously it was skipping over implicit operands which
cause infinite looping when the two-address pass try to reschedule a
two-address instruction below the kill of tied operand.
I'm unable to come up with a reasonably sized test case.
rdar://13747577
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180906 91177308-0d34-0410-b5e6-96231b3b80d8
function is successfully handled by fast-isel. That's because function
arguments are *always* handled by SDISel. Introduce FastLowerArguments to
allow each target to provide hook to handle formal argument lowering.
As a proof-of-concept, add ARMFastIsel::FastLowerArguments to handle
functions with 4 or fewer scalar integer (i8, i16, or i32) arguments. It
completely eliminates the need for SDISel for trivial functions.
rdar://13163905
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174855 91177308-0d34-0410-b5e6-96231b3b80d8
conditions are met:
1. They share the same operand and are in the same BB.
2. Both outputs are used.
3. The target has a native instruction that maps to ISD::FSINCOS node or
the target provides a sincos library call.
Implemented the generic optimization in sdisel and enabled it for
Mac OSX. Also added an additional optimization for x86_64 Mac OSX by
using an alternative entry point __sincos_stret which returns the two
results in xmm0 / xmm1.
rdar://13087969
PR13204
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173755 91177308-0d34-0410-b5e6-96231b3b80d8
It cahced XOR's operands before calling visitXOR() but failed to update the
operands when visitXOR changed the XOR node.
rdar://12968664
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171999 91177308-0d34-0410-b5e6-96231b3b80d8
are more expensive than the non-flag setting variant. Teach thumb2 size
reduction pass to avoid generating them unless we are optimizing for size.
rdar://12892707
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170728 91177308-0d34-0410-b5e6-96231b3b80d8
((x & 0xff00) >> 8) << 2
to
(x >> 6) & 0x3fc
This is general goodness since it folds a left shift into the mask. However,
the trailing zeros in the mask prevents the ARM backend from using the bit
extraction instructions. And worse since the mask materialization may require
an addition instruction. This comes up fairly frequently when the result of
the bit twiddling is used as memory address. e.g.
= ptr[(x & 0xFF0000) >> 16]
We want to generate:
ubfx r3, r1, #16, #8
ldr.w r3, [r0, r3, lsl #2]
vs.
mov.w r9, #1020
and.w r2, r9, r1, lsr #14
ldr r2, [r0, r2]
Add a late ARM specific isel optimization to
ARMDAGToDAGISel::PreprocessISelDAG(). It folds the left shift to the
'base + offset' address computation; change the mask to one which doesn't have
trailing zeros and enable the use of ubfx.
Note the optimization has to be done late since it's target specific and we
don't want to change the DAG normalization. It's also fairly restrictive
as shifter operands are not always free. It's only done for lsh 1 / 2. It's
known to be free on some cpus and they are most common for address
computation.
This is a slight win for blowfish, rijndael, etc.
rdar://12870177
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170581 91177308-0d34-0410-b5e6-96231b3b80d8
load / store pair. It's not legal to use a wider load than the size of
the remaining bytes if it's the first pair of load / store.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170018 91177308-0d34-0410-b5e6-96231b3b80d8
mention the inline memcpy / memset expansion code is a mess?
This patch split the ZeroOrLdSrc argument into two: IsMemset and ZeroMemset.
The first indicates whether it is expanding a memset or a memcpy / memmove.
The later is whether the memset is a memset of zero. It's totally possible
(likely even) that targets may want to do different things for memcpy and
memset of zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169959 91177308-0d34-0410-b5e6-96231b3b80d8
Also added more comments to explain why it is generally ok to return true.
- Rename getOptimalMemOpType argument IsZeroVal to ZeroOrLdSrc. It's meant to
be true for loaded source (memcpy) or zero constants (memset). The poor name
choice is probably some kind of legacy issue.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169954 91177308-0d34-0410-b5e6-96231b3b80d8
ScalarTargetTransformInfo::getIntImmCost() instead. "Legal" is a poorly defined
term for something like integer immediate materialization. It is always possible
to materialize an integer immediate. Whether to use it for memcpy expansion is
more a "cost" conceern.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169929 91177308-0d34-0410-b5e6-96231b3b80d8
1. Teach it to use overlapping unaligned load / store to copy / set the trailing
bytes. e.g. On 86, use two pairs of movups / movaps for 17 - 31 byte copies.
2. Use f64 for memcpy / memset on targets where i64 is not legal but f64 is. e.g.
x86 and ARM.
3. When memcpy from a constant string, do *not* replace the load with a constant
if it's not possible to materialize an integer immediate with a single
instruction (required a new target hook: TLI.isIntImmLegal()).
4. Use unaligned load / stores more aggressively if target hooks indicates they
are "fast".
5. Update ARM target hooks to use unaligned load / stores. e.g. vld1.8 / vst1.8.
Also increase the threshold to something reasonable (8 for memset, 4 pairs
for memcpy).
This significantly improves Dhrystone, up to 50% on ARM iOS devices.
rdar://12760078
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169791 91177308-0d34-0410-b5e6-96231b3b80d8
understand target implementation of any_extend / extload, just generate
zero_extend in place of any_extend for liveouts when the target knows the
zero_extend will be implicit (e.g. ARM ldrb / ldrh) or folded (e.g. x86 movz).
rdar://12771555
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169536 91177308-0d34-0410-b5e6-96231b3b80d8
the tables cannot fit in registers (i.e. bitmap), do not emit the table
if it's using an illegal type.
rdar://12779436
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168970 91177308-0d34-0410-b5e6-96231b3b80d8
getNumContainedPasses() used to compute the size of the vector on demand. It is
called repeated in loops (such as runOnFunction()) and it can be updated while
inside the loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167759 91177308-0d34-0410-b5e6-96231b3b80d8
mov lr, pc
b.w _foo
The "mov" instruction doesn't set bit zero to one, it's putting incorrect
value in lr. It messes up backtraces.
rdar://12663632
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167657 91177308-0d34-0410-b5e6-96231b3b80d8
into a sbc with a positive number, the immediate should be complemented, not
negated. Also added a missing pattern for ARM codegen.
rdar://12559385
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166613 91177308-0d34-0410-b5e6-96231b3b80d8
any scheduling heuristics nor does it build up any scheduling data structure
that other heuristics use. It essentially linearize by doing a DFA walk but
it does handle glues correctly.
IMPORTANT: it probably can't handle all the physical register dependencies so
it's not suitable for x86. It also doesn't deal with dbg_value nodes right now
so it's definitely is still WIP.
rdar://12474515
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166122 91177308-0d34-0410-b5e6-96231b3b80d8
not legal. However, it should use a div instruction + mul + sub if divide is
legal. The rem legalization code was missing a check and incorrectly uses a
divrem libcall even when div is legal.
rdar://12481395
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165778 91177308-0d34-0410-b5e6-96231b3b80d8
X86DAGToDAGISel::PreprocessISelDAG(), isel is moving load inside
callseq_start / callseq_end so it can be folded into a call. This can
create a cycle in the DAG when the call is glued to a copytoreg. We
have been lucky this hasn't caused too many issues because the pre-ra
scheduler has special handling of call sequences. However, it has
caused a crash in a specific tailcall case.
rdar://12393897
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165072 91177308-0d34-0410-b5e6-96231b3b80d8
because LiveStackAnalysis was not preserved by VirtRegWriter. This caused
big stack usage regression in some cases.
rdar://12340383
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164408 91177308-0d34-0410-b5e6-96231b3b80d8
aligned address. Based on patch by David Peixotto.
Also use vld1.64 / vst1.64 with 128-bit alignment to take advantage of alignment
hints. rdar://12090772, rdar://12238782
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164089 91177308-0d34-0410-b5e6-96231b3b80d8
large immediates. Add dag combine logic to recover in case the large
immediates doesn't fit in cmp immediate operand field.
int foo(unsigned long l) {
return (l>> 47) == 1;
}
we produce
%shr.mask = and i64 %l, -140737488355328
%cmp = icmp eq i64 %shr.mask, 140737488355328
%conv = zext i1 %cmp to i32
ret i32 %conv
which codegens to
movq $0xffff800000000000,%rax
andq %rdi,%rax
movq $0x0000800000000000,%rcx
cmpq %rcx,%rax
sete %al
movzbl %al,%eax
ret
TargetLowering::SimplifySetCC would transform
(X & -256) == 256 -> (X >> 8) == 1
if the immediate fails the isLegalICmpImmediate() test. For x86,
that's immediates which are not a signed 32-bit immediate.
Based on a patch by Eli Friedman.
PR10328
rdar://9758774
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160346 91177308-0d34-0410-b5e6-96231b3b80d8
uint32_t hi(uint64_t res)
{
uint_32t hi = res >> 32;
return !hi;
}
llvm IR looks like this:
define i32 @hi(i64 %res) nounwind uwtable ssp {
entry:
%lnot = icmp ult i64 %res, 4294967296
%lnot.ext = zext i1 %lnot to i32
ret i32 %lnot.ext
}
The optimizer has optimize away the right shift and truncate but the resulting
constant is too large to fit in the 32-bit immediate field. The resulting x86
code is worse as a result:
movabsq $4294967296, %rax ## imm = 0x100000000
cmpq %rax, %rdi
sbbl %eax, %eax
andl $1, %eax
This patch teaches the x86 lowering code to handle ult against a large immediate
with trailing zeros. It will issue a right shift and a truncate followed by
a comparison against a shifted immediate.
shrq $32, %rdi
testl %edi, %edi
sete %al
movzbl %al, %eax
It also handles a ugt comparison against a large immediate with trailing bits
set. i.e. X > 0x0ffffffff -> (X >> 32) >= 1
rdar://11866926
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160312 91177308-0d34-0410-b5e6-96231b3b80d8
%shr = lshr i64 %key, 3
%0 = load i64* %val, align 8
%sub = add i64 %0, -1
%and = and i64 %sub, %shr
ret i64 %and
to:
%shr = lshr i64 %key, 3
%0 = load i64* %val, align 8
%sub = add i64 %0, 2305843009213693951
%and = and i64 %sub, %shr
ret i64 %and
The demanded bit optimization is actually a pessimization because add -1 would
be codegen'ed as a sub 1. Teach the demanded constant shrinking optimization
to check for negated constant to make sure it is actually reducing the width
of the constant.
rdar://11793464
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160101 91177308-0d34-0410-b5e6-96231b3b80d8
r1025 = s/zext r1024, 4
r1026 = extract_subreg r1025, 4
to a copy:
r1026 = copy r1024
This is correct. However it uses TII->isCoalescableExtInstr() which can return
true for instructions which essentially does a sext_in_reg so this can end up
with an illegal copy where the source and destination register classes do not
match. Add a check to avoid it. Sorry, no test case possible at this time.
rdar://11849816
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160059 91177308-0d34-0410-b5e6-96231b3b80d8
// C - zext(bool) -> bool ? C - 1 : C
if (ZExtInst *ZI = dyn_cast<ZExtInst>(Op1))
if (ZI->getSrcTy()->isIntegerTy(1))
return SelectInst::Create(ZI->getOperand(0), SubOne(C), C);
This ends up forming sext i1 instructions that codegen to terrible code. e.g.
int blah(_Bool x, _Bool y) {
return (x - y) + 1;
}
=>
movzbl %dil, %eax
movzbl %sil, %ecx
shll $31, %ecx
sarl $31, %ecx
leal 1(%rax,%rcx), %eax
ret
Without the rule, llvm now generates:
movzbl %sil, %ecx
movzbl %dil, %eax
incl %eax
subl %ecx, %eax
ret
It also helps with ARM (and pretty much any target that doesn't have a sext i1 :-).
The transformation was done as part of Eli's r75531. He has given the ok to
remove it.
rdar://11748024
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159230 91177308-0d34-0410-b5e6-96231b3b80d8
There are patterns to handle immediates when they fit in the immediate field.
e.g. %sub = add i32 %x, -123
=> sub r0, r0, #123
Add patterns to catch immediates that do not fit but should be materialized
with a single movw instruction rather than movw + movt pair.
e.g. %sub = add i32 %x, -65535
=> movw r1, #65535
sub r0, r0, r1
rdar://11726136
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159057 91177308-0d34-0410-b5e6-96231b3b80d8
_umodsi3 libcalls if they have the same arguments. This optimization
was apparently broken if one of the node was replaced in place.
rdar://11714607
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158900 91177308-0d34-0410-b5e6-96231b3b80d8
non-profitable commute using outdated info. The test case would still fail
because of poor pre-RA schedule. That will be fixed by MI scheduler.
rdar://11472010
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157038 91177308-0d34-0410-b5e6-96231b3b80d8
to catch cases like:
%reg1024<def> = MOV r1
%reg1025<def> = MOV r0
%reg1026<def> = ADD %reg1024, %reg1025
r0 = MOV %reg1026
By commuting ADD, it let coalescer eliminate all of the copies. However, there
was a bug in the heuristics where it ended up commuting the ADD in:
%reg1024<def> = MOV r0
%reg1025<def> = MOV 0
%reg1026<def> = ADD %reg1024, %reg1025
r0 = MOV %reg1026
That did no benefit but rather ensure the last MOV would not be coalesced.
rdar://11355268
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156048 91177308-0d34-0410-b5e6-96231b3b80d8
the feature set of v7a. This comes about if the user specifies something like
-arch armv7 -mcpu=cortex-m3. We shouldn't be generating instructions such as
uxtab in this case.
rdar://11318438
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155601 91177308-0d34-0410-b5e6-96231b3b80d8
Evan Cheng