The greedy register allocator tries to split a live-range around each
instruction where it is used or defined to relax the constraints on the entire
live-range (this is a last chance split before falling back to spill).
The goal is to have a big live-range that is unconstrained (i.e., that can use
the largest legal register class) and several small local live-range that carry
the constraints implied by each instruction.
E.g.,
Let csti be the constraints on operation i.
V1=
op1 V1(cst1)
op2 V1(cst2)
V1 live-range is constrained on the intersection of cst1 and cst2.
tryInstructionSplit relaxes those constraints by aggressively splitting each
def/use point:
V1=
V2 = V1
V3 = V2
op1 V3(cst1)
V4 = V2
op2 V4(cst2)
Because of how the coalescer infrastructure works, each new variable (V3, V4)
that is alive at the same time as V1 (or its copy, here V2) interfere with V1.
Thus, we end up with an uncoalescable copy for each split point.
To make tryInstructionSplit less aggressive, we check if the split point
actually relaxes the constraints on the whole live-range. If it does not, we do
not insert it.
Indeed, it will not help the global allocation problem:
- V1 will have the same constraints.
- V1 will have the same interference + possibly the newly added split variable
VS.
- VS will produce an uncoalesceable copy if alive at the same time as V1.
<rdar://problem/15570057>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198369 91177308-0d34-0410-b5e6-96231b3b80d8
This patch makes it possible to select the ABI with -mattr. It will be used to
forward clang's -target-abi option to llvm's CodeGen.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198304 91177308-0d34-0410-b5e6-96231b3b80d8
For AArch64 backend, if DAGCombiner see "sext(setcc)", it will
combine them together to a single setcc with extended value type.
Then if it see "zext(setcc)", it assumes setcc is Vxi1, and try to
create "(and (vsetcc), (1, 1, ...)". While setcc isn't Vxi1,
DAGcombiner will create wrong node and get wrong code emitted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198190 91177308-0d34-0410-b5e6-96231b3b80d8
Schedule more conservatively to account for stalls on floating point
resources and latency. Use the AGU resource to model latency stalls
since it's shared between FP and LD/ST instructions. This might not be
completely accurate but should work well in practice.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198125 91177308-0d34-0410-b5e6-96231b3b80d8
vector shift by immedate count (VSHLI/VSRLI/VSRAI) into a build_vector when
the vector in input to the shift is a build_vector of all constants or UNDEFs.
Target specific nodes for packed shifts by immediate count are in
general introduced by function 'getTargetVShiftByConstNode' (in
X86ISelLowering.cpp) when lowering shift operations, SSE/AVX immediate
shift intrinsics and (only in very few cases) SIGN_EXTEND_INREG dag
nodes.
This patch adds extra rules for simplifying vector shifts inside
function 'getTargetVShiftByConstNode'.
Added file test/CodeGen/X86/vec_shift5.ll to verify that packed
shifts by immediate are correctly folded into a build_vector when the
input vector to the shift dag node is a vector of constants or undefs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198113 91177308-0d34-0410-b5e6-96231b3b80d8
ConstantSDNodes (or UNDEFs) into a simple BUILD_VECTOR.
For example, given the following sequence of dag nodes:
i32 C = Constant<1>
v4i32 V = BUILD_VECTOR C, C, C, C
v4i32 Result = SIGN_EXTEND_INREG V, ValueType:v4i1
The SIGN_EXTEND_INREG node can be folded into a build_vector since
the vector in input is a BUILD_VECTOR of constants.
The optimized sequence is:
i32 C = Constant<-1>
v4i32 Result = BUILD_VECTOR C, C, C, C
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198084 91177308-0d34-0410-b5e6-96231b3b80d8
E.g. the codegen result is
fmls v1.2s, v0.2s, v2.s[3]
which is expected to be
fmls v0.2s, v1.2s, v2.s[3]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198001 91177308-0d34-0410-b5e6-96231b3b80d8
...namely LOAD AND ADD, LOAD AND AND, LOAD AND OR and LOAD AND EXCLUSIVE OR.
LOAD AND ADD LOGICAL isn't really separately useful for LLVM.
I'll look at adding reusing the CC results in new year.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197985 91177308-0d34-0410-b5e6-96231b3b80d8
DAG.getVectorShuffle() doesn't always return a vector_shuffle node.
If mask is the exact sequence of it's operand(For example, operand_0
is v8i8, and the mask is 0, 1, 2, 3, 4, 5, 6, 7), it will directly
return that operand. So a check is added here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197967 91177308-0d34-0410-b5e6-96231b3b80d8
This failure caused by improper condition when lowering shuffle_vector
to scalar_to_vector. After this patch NEON_VDUP with v1i64 will not
be generated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197966 91177308-0d34-0410-b5e6-96231b3b80d8
Check for single use of fmul node in fused multiply patterns
to allow generation of fused multiply add/sub instructions.
Otherwise fmul operation ends up being repeated more than
once which does not help peformance on targets with
only one MAC unit, as for example cortex-a53.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197929 91177308-0d34-0410-b5e6-96231b3b80d8
The correct pattern matching should be:
- fnmadd is (-Ra) + (-Rn)*Rm which should be matched as:
fma (fneg node:$Rn), node:$Rm, (fneg node:$Ra) and as
(f32 (fsub (f32 (fneg FPR32:$Ra)), (f32 (fmul FPR32:$Rn, FPR32:$Rm))))
- fnmsub is (-Ra) + Rn*Rm which should be matched as
fma node:$Rn, node:$Rm, (fneg node:$Ra) and as
(f32 (fsub (f32 (fmul FPR32:$Rn, FPR32:$Rm)), FPR32:$Ra))))
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197928 91177308-0d34-0410-b5e6-96231b3b80d8
If the extension of a loaded value is compared against zero and used in
other arithmetic, InstCombine will change the comparison to use the
unextended load. It's also possible that the comparison could be against
the unextended load from the outset.
In DAG form this becomes a truncation of an extending load. We want to
strip the truncation if possible so that we can use load-and-test instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197804 91177308-0d34-0410-b5e6-96231b3b80d8
The handling of ANY_EXTEND and ZERO_EXTEND was too strict. In this context
we can treat ZERO_EXTEND in much the same way as an AND and then also handle
outermost ZERO_EXTENDs.
I couldn't find a test that benefited from the ANY_EXTEND change, but it's
more obvious to write it this way once SIGN_EXTEND and ZERO_EXTEND are
handled differently.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197802 91177308-0d34-0410-b5e6-96231b3b80d8
v2: Add ftrunc->TRUNC pattern instead of replacing int_AMDGPU_trunc
v3: move ftrunc pattern next to TRUNC definition, it's available since R600
Patch By: Jan Vesely
Reviewed-by: Tom Stellard <thomas.stellard@amd.com>
Signed-off-by: Jan Vesely <jan.vesely@rutgers.edu>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197783 91177308-0d34-0410-b5e6-96231b3b80d8
The condition in selects is supposed to be i1.
Make sure we are just reading the less significant bit
of the 8 bits width value to match this constraint.
<rdar://problem/15651765>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197712 91177308-0d34-0410-b5e6-96231b3b80d8
Different sized address spaces should theoretically work
most of the time now, and since 64-bit add is currently
disabled, using more 32-bit pointers fixes some cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197659 91177308-0d34-0410-b5e6-96231b3b80d8
This changes the MachineFrameInfo API to use the new SSPLayoutKind information
produced by the StackProtector pass (instead of a boolean flag) and updates a
few pass dependencies (to preserve the SSP analysis).
The stack layout follows the same approach used prior to this change - i.e.,
only LargeArray stack objects will be placed near the canary and everything
else will be laid out normally. After this change, structures containing large
arrays will also be placed near the canary - a case previously missed by the
old implementation.
Out of tree targets will need to update their usage of
MachineFrameInfo::CreateStackObject to remove the MayNeedSP argument.
The next patch will implement the rules for sspstrong and sspreq. The end goal
is to support ssp-strong stack layout rules.
WIP.
Differential Revision: http://llvm-reviews.chandlerc.com/D2158
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197653 91177308-0d34-0410-b5e6-96231b3b80d8
The inalloca attribute is designed to support passing C++ objects by
value in the Microsoft C++ ABI. It behaves the same as byval, except
that it always implies that the argument is in memory and that the bytes
are never copied. This attribute allows the caller to take the address
of an outgoing argument's memory and execute arbitrary code to store
into it.
This patch adds basic IR support, docs, and verification. It does not
attempt to implement any lowering or fix any possibly broken transforms.
When this patch lands, a complete description of this feature should
appear at http://llvm.org/docs/InAlloca.html .
Differential Revision: http://llvm-reviews.chandlerc.com/D2173
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197645 91177308-0d34-0410-b5e6-96231b3b80d8
tail call optimization. Some more work may be needed for indirect
calls but this patch fixes the current regression in Prolangc++/trees.
S2 optimization as part of the general cleanup and optimization
of prolog and epilog was not saving S2 in this case and needed to.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197630 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r197466.
The MachineCSE fix that required the -mcpu flag has been disabled
until more work can be done to fix downstream issues. Adding -mcpu
wasn't the right workaround anyway.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197624 91177308-0d34-0410-b5e6-96231b3b80d8
Given vsel_cc, op1, op2, since vsel has no LE/LT, to generate vsel for
such selection, it needs to inverse cc and swap op1 and op2. To inverse
cc, both L/G and E bits should be flipped.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197615 91177308-0d34-0410-b5e6-96231b3b80d8
Clang sets the float-abi target option manually, but no longer
annotates each function with its ABI. This can lead to confusing
mistmatch between "clang -emit-llvm | llc" and normal clang
invocations.
Besides which, gnueabihf actually *is* hard-float. Defaulting to soft
was just perverse.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197554 91177308-0d34-0410-b5e6-96231b3b80d8
