Those can occur when something between the sextload and the store is on the same
chain and blocks isel. Fixes PR14887.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172353 91177308-0d34-0410-b5e6-96231b3b80d8
Adds a check for -Oz, changes the code to not re-visit BBs,
and skips over DBG_VALUE instrs.
Patch by Andy Zhang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172258 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
PR 14848. The lowered sequence is based on the existing sequence the target-independent
DAG Combiner creates for the scalar case.
Patch by Zvi Rackover.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171953 91177308-0d34-0410-b5e6-96231b3b80d8
The current Intel Atom microarchitecture has a feature whereby
when a function returns early then it is slightly faster to execute
a sequence of NOP instructions to wait until the return address is ready,
as opposed to simply stalling on the ret instruction until
the return address is ready.
When compiling for X86 Atom only, this patch will run a pass,
called "X86PadShortFunction" which will add NOP instructions where less
than four cycles elapse between function entry and return.
It includes tests.
This patch has been updated to address Nadav's review comments
- Optimize only at >= O1 and don't do optimization if -Os is set
- Stores MachineBasicBlock* instead of BBNum
- Uses DenseMap instead of std::map
- Fixes placement of braces
Patch by Andy Zhang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171879 91177308-0d34-0410-b5e6-96231b3b80d8
cvtsi2* should parse with an 'l' or 'q' suffix or no suffix at all. No suffix should be treated the same as 'l' suffix. Printing should always print a suffix. Previously we didn't parse or print an 'l' suffix.
cvtt*2si/cvt*2si should parse with an 'l' or 'q' suffix or not suffix at all. No suffix should use the destination register size to choose encoding. Printing should not print a suffix.
Original 'l' suffix issue with cvtsi2* pointed out by Michael Kuperstein.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171668 91177308-0d34-0410-b5e6-96231b3b80d8
URL: http://llvm.org/viewvc/llvm-project?rev=171524&view=rev
Log:
The current Intel Atom microarchitecture has a feature whereby when a function
returns early then it is slightly faster to execute a sequence of NOP
instructions to wait until the return address is ready,
as opposed to simply stalling on the ret instruction
until the return address is ready.
When compiling for X86 Atom only, this patch will run a pass, called
"X86PadShortFunction" which will add NOP instructions where less than four
cycles elapse between function entry and return.
It includes tests.
Patch by Andy Zhang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171603 91177308-0d34-0410-b5e6-96231b3b80d8
returns early then it is slightly faster to execute a sequence of NOP
instructions to wait until the return address is ready,
as opposed to simply stalling on the ret instruction
until the return address is ready.
When compiling for X86 Atom only, this patch will run a pass, called
"X86PadShortFunction" which will add NOP instructions where less than four
cycles elapse between function entry and return.
It includes tests.
Patch by Andy Zhang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171524 91177308-0d34-0410-b5e6-96231b3b80d8
Simplified TRUNCATE operation that comes after SETCC. It is possible since SETCC result is 0 or -1.
Added a test.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171468 91177308-0d34-0410-b5e6-96231b3b80d8
Most IMPLICIT_DEF instructions are removed by the ProcessImplicitDefs
pass, and a few are reinserted by PHIElimination when a PHI argument is
<undef>.
RegisterCoalescer was assuming that all IMPLICIT_DEF live ranges look
like those created by PHIElimination, and that their live range never
leaves the basic block.
The PR14732 test case does tricks with PHI nodes that causes a longer
IMPLICIT_DEF live range to appear. This happens very rarely, but
RegisterCoalescer should be able to handle it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171435 91177308-0d34-0410-b5e6-96231b3b80d8
DAGCombiner::reduceBuildVecConvertToConvertBuildVec() was making two
mistakes:
1. It was checking the legality of scalar INT_TO_FP nodes and then generating
vector nodes.
2. It was passing the result value type to
TargetLoweringInfo::getOperationAction() when it should have been
passing the value type of the first operand.
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register. In most cases we actually compare or select YMM-sized registers
and mixing the two types creates horrible code. This commit optimizes
some of the transition sequences.
PR14657.
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When these instructions are encoded in VEX (on AVX) there is no such requirement. This changes the folding
tables and removes the alignment restrictions from VEX-encoded instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171024 91177308-0d34-0410-b5e6-96231b3b80d8
pmuludq is slow, but it turns out that all the unpacking and packing of the
scalarized mul is even slower. 10% speedup on loop-vectorized paq8p.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170985 91177308-0d34-0410-b5e6-96231b3b80d8
Also loosen the SSSE3 dependency a bit, expanded pshufb + psra is still better
than scalarized loads. Fixes PR14590.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170984 91177308-0d34-0410-b5e6-96231b3b80d8
The only way to read the eflags is using push and pop. If we don't
adjust the stack then we run over the first frame index. This is
not something that we want to do, so we have to make sure that
our machine function does not copy the flags. If it does then
we have to emit the prolog that adjusts the stack.
rdar://12896831
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170961 91177308-0d34-0410-b5e6-96231b3b80d8
We match the pattern "x >= y ? x-y : 0" into "subus x, y" and two special cases
if y is a constant. DAGCombiner canonicalizes those so we first have to undo the
canonicalization for those cases. The pattern occurs in gzip when the loop
vectorizer is enabled. Part of PR14613.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170273 91177308-0d34-0410-b5e6-96231b3b80d8
try to reduce the width of this load, and would end up transforming:
(truncate (lshr (sextload i48 <ptr> as i64), 32) to i32)
to
(truncate (zextload i32 <ptr+4> as i64) to i32)
We lost the sext attached to the load while building the narrower i32
load, and replaced it with a zext because lshr always zext's the
results. Instead, bail out of this combine when there is a conflict
between a sextload and a zext narrowing. The rest of the DAG combiner
still optimize the code down to the proper single instruction:
movswl 6(...),%eax
Which is exactly what we wanted. Previously we read past the end *and*
missed the sign extension:
movl 6(...), %eax
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169802 91177308-0d34-0410-b5e6-96231b3b80d8
This shouldn't affect codegen for -O0 compiles as tail call markers are not
emitted in unoptimized compiles. Testing with the external/internal nightly
test suite reveals no change in compile time performance. Testing with -O1,
-O2 and -O3 with fast-isel enabled did not cause any compile-time or
execution-time failures. All tests were performed on my x86 machine.
I'll monitor our arm testers to ensure no regressions occur there.
In an upcoming clang patch I will be marking the objc_autoreleaseReturnValue
and objc_retainAutoreleaseReturnValue as tail calls unconditionally. While
it's theoretically true that this is just an optimization, it's an
optimization that we very much want to happen even at -O0, or else ARC
applications become substantially harder to debug.
Part of rdar://12553082
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169796 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
the VSRI instruction before it since it does not affect the MSB.
Thanks Craig Topper for suggesting this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169638 91177308-0d34-0410-b5e6-96231b3b80d8
check if loads that happen in between stores alias with the first store in the
chain, only with the second store onwards.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169516 91177308-0d34-0410-b5e6-96231b3b80d8
This is much simpler to reason about, more efficient, and
fixes some corner cases involving implicit super-register defs.
Fixed rdar://12797931.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169425 91177308-0d34-0410-b5e6-96231b3b80d8
The count attribute is more accurate with regards to the size of an array. It
also obviates the upper bound attribute in the subrange. We can also better
handle an unbound array by setting the count to -1 instead of the lower bound to
1 and upper bound to 0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169312 91177308-0d34-0410-b5e6-96231b3b80d8
The count field is necessary because there isn't a difference between the 'lo'
and 'hi' attributes for a one-element array and a zero-element array. When the
count is '0', we know that this is a zero-element array. When it's >=1, then
it's a normal constant sized array. When it's -1, then the array is unbounded.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169218 91177308-0d34-0410-b5e6-96231b3b80d8
This is a simple, cheap infrastructure for analyzing the shape of a
DAG. It recognizes uniform DAGs that take the shape of bottom-up
subtrees, such as the included matrix multiplication example. This is
useful for heuristics that balance register pressure with ILP. Two
canonical expressions of the heuristic are implemented in scheduling
modes: -misched-ilpmin and -misched-ilpmax.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168773 91177308-0d34-0410-b5e6-96231b3b80d8
This fixes a hole in the "cheap" alias analysis logic implemented within
the DAG builder itself, regardless of whether proper alias analysis is
enabled. It now handles this pattern produced by LSR+CodeGenPrepare.
%sunkaddr1 = ptrtoint * %obj to i64
%sunkaddr2 = add i64 %sunkaddr1, %lsr.iv
%sunkaddr3 = inttoptr i64 %sunkaddr2 to i32*
store i32 %v, i32* %sunkaddr3
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168768 91177308-0d34-0410-b5e6-96231b3b80d8
when the destination register is wider than the memory load.
These load instructions load from m32 or m64 and set the upper bits to zero,
while the folded instructions may accept m128.
rdar://12721174
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168710 91177308-0d34-0410-b5e6-96231b3b80d8
This pass was conservative in that it always reserved the FP to enable dynamic
stack realignment, which allowed the RA to use aligned spills for vector
registers. This happens even when spills were not necessary. The RA has
since been improved to use unaligned spills when necessary.
The new behavior is to realign the stack if the frame pointer was already
reserved for some other reason, but don't reserve the frame pointer just
because a function contains vector virtual registers.
Part of rdar://12719844
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168627 91177308-0d34-0410-b5e6-96231b3b80d8
The stack realignment code was fixed to work when there is stack realignment and
a dynamic alloca is present so this shouldn't cause correctness issues anymore.
Note that this also enables generation of AVX instructions for memset
under the assumptions:
- Unaligned loads/stores are always fast on CPUs supporting AVX
- AVX is not slower than SSE
We may need some tweaked heuristics if one of those assumptions turns out not to
be true.
Effectively reverts r58317. Part of PR2962.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167967 91177308-0d34-0410-b5e6-96231b3b80d8
temporarily as it is breaking the gdb bots.
This reverts commit r167806/e7ff4c14b157746b3e0228d2dce9f70712d1c126.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167886 91177308-0d34-0410-b5e6-96231b3b80d8
chain is correctly setup.
As an example, if the original load must happen before later stores, we need
to make sure the constructed VZEXT_LOAD is constrained to be before the stores.
rdar://12684358
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167859 91177308-0d34-0410-b5e6-96231b3b80d8
If we have a type 'int a[1]' and a type 'int b[0]', the generated DWARF is the
same for both of them because we use the 'upper_bound' attribute. Instead use
the 'count' attrbute, which gives the correct number of elements in the array.
<rdar://problem/12566646>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167806 91177308-0d34-0410-b5e6-96231b3b80d8
- Fix operand order for atomic sub, where the minuend is the value
loaded from memory and the subtrahend is the parameter specified.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167718 91177308-0d34-0410-b5e6-96231b3b80d8
- Add RTM code generation support throught 3 X86 intrinsics:
xbegin()/xend() to start/end a transaction region, and xabort() to abort a
tranaction region
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167573 91177308-0d34-0410-b5e6-96231b3b80d8
misched is disabled by default. With -enable-misched, these heuristics
balance the schedule to simultaneously avoid saturating processor
resources, expose ILP, and minimize register pressure. I've been
analyzing the performance of these heuristics on everything in the
llvm test suite in addition to a few other benchmarks. I would like
each heuristic check to be verified by a unit test, but I'm still
trying to figure out the best way to do that. The heuristics are still
in considerable flux, but as they are refined we should be rigorous
about unit testing the improvements.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167527 91177308-0d34-0410-b5e6-96231b3b80d8
The adc/sbb optimization is to able to convert following expression
into a single adc/sbb instruction:
(ult) ... = x + 1 // where the ult is unsigned-less-than comparison
(ult) ... = x - 1
This change is to flip the "x >u y" (i.e. ugt comparison) in order
to expose the adc/sbb opportunity.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167180 91177308-0d34-0410-b5e6-96231b3b80d8
the first source operand is tied to the destination operand.
This is to accurately model the corresponding instructions where the upper
bits are unmodified.
rdar://12558838
PR14221
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167064 91177308-0d34-0410-b5e6-96231b3b80d8
incorrect instruction sequence due to it not being aware that an
inline assembly instruction may reference memory.
This patch fixes the problem by causing the scheduler to always assume that any
inline assembly code instruction could access memory. This is necessary because
the internal representation of the inline instruction does not include
any information about memory accesses.
This should fix PR13504.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166929 91177308-0d34-0410-b5e6-96231b3b80d8
- If more than 1 elemennts are defined and target supports the vectorized
conversion, use the vectorized one instead to reduce the strength on
conversion operation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166546 91177308-0d34-0410-b5e6-96231b3b80d8
- As there's no 64-bit GPRs in 32-bit mode, a custom conversion from v2u32 to
v2f32 is added to improve the efficiency of the code generated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166545 91177308-0d34-0410-b5e6-96231b3b80d8
the difference from "int x" (which should go in registers and
"struct y {int x;}" (which should not).
Clang will be updated in the next patches.
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- Check index being extracted to be constant 0 before simplfiying.
Otherwise, retain the original sequence.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166504 91177308-0d34-0410-b5e6-96231b3b80d8
- If INSERT_VECTOR_ELT is supported (above SSE2, either by custom
sequence of legal insn), transform BUILD_VECTOR into SHUFFLE +
INSERT_VECTOR_ELT if most of elements could be built from SHUFFLE with few
(so far 1) elements being inserted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166288 91177308-0d34-0410-b5e6-96231b3b80d8
When merging stack slots, if StackColoring::remapInstructions gets a
value back from GetUnderlyingObject that it does not know about or is
not itself a stack slot, clear the memory operand in case it aliases
the merged slot. This prevents the introduction of incorrect aliasing
information.
Author: Matthew Curtis <mcurtis@codeaurora.org>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166216 91177308-0d34-0410-b5e6-96231b3b80d8
- Folding (trunc (concat ... X )) to (concat ... (trunc X) ...) is valid
when '...' are all 'undef's.
- r166125 relies on this transformation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166155 91177308-0d34-0410-b5e6-96231b3b80d8
- If the extracted vector has the same type of all vectored being concatenated
together, it should be simplified directly into v_i, where i is the index of
the element being extracted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166125 91177308-0d34-0410-b5e6-96231b3b80d8
- MBB address is only valid as an immediate value in Small & Static
code/relocation models. On other models, LEA is needed to load IP address of
the restore MBB.
- A minor fix of MBB in MC lowering is added as well to enable target
relocation flag being propagated into MC.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166084 91177308-0d34-0410-b5e6-96231b3b80d8
PR14098 contains an example where we would rematerialize a MOV8ri
immediately after the original instruction:
%vreg7:sub_8bit<def> = MOV8ri 9; GR32_ABCD:%vreg7
%vreg22:sub_8bit<def> = MOV8ri 9; GR32_ABCD:%vreg7
Besides being pointless, it is also wrong since the original instruction
only redefines part of the register, and the value read by the new
instruction is wrong.
The problem was the LiveRangeEdit::allUsesAvailableAt() didn't
special-case OrigIdx == UseIdx and found the wrong SSA value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166068 91177308-0d34-0410-b5e6-96231b3b80d8
Original message:
The attached is the fix to radar://11663049. The optimization can be outlined by following rules:
(select (x != c), e, c) -> select (x != c), e, x),
(select (x == c), c, e) -> select (x == c), x, e)
where the <c> is an integer constant.
The reason for this change is that : on x86, conditional-move-from-constant needs two instructions;
however, conditional-move-from-register need only one instruction.
While the LowerSELECT() sounds to be the most convenient place for this optimization, it turns out to be a bad place. The reason is that by replacing the constant <c> with a symbolic value, it obscure some instruction-combining opportunities which would otherwise be very easy to spot. For that reason, I have to postpone the change to last instruction-combining phase.
The change passes the test of "make check-all -C <build-root/test" and "make -C project/test-suite/SingleSource".
Original message since r165661:
My previous change has a bug: I negated the condition code of a CMOV, and go ahead creating a new CMOV using the *ORIGINAL* condition code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166017 91177308-0d34-0410-b5e6-96231b3b80d8
This is a medium term workaround until we have a more robust solution
in the form of a register liveness utility for postRA passes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166001 91177308-0d34-0410-b5e6-96231b3b80d8
- Besides used in SjLj exception handling, __builtin_setjmp/__longjmp is also
used as a light-weight replacement of setjmp/longjmp which are used to
implementation continuation, user-level threading, and etc. The support added
in this patch ONLY addresses this usage and is NOT intended to support SjLj
exception handling as zero-cost DWARF exception handling is used by default
in X86.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165989 91177308-0d34-0410-b5e6-96231b3b80d8
X86 doesn't have i8 cmovs so isel would emit a branch. Emitting branches at this
level is often not a good idea because it's too late for many optimizations to
kick in. This solution doesn't add any extensions (truncs are free) and tries
to avoid introducing partial register stalls by filtering direct copyfromregs.
I'm seeing a ~10% speedup on reading a random .png file with libpng15 via
graphicsmagick on x86_64/westmere, but YMMV depending on the microarchitecture.
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