Resolve Bug 27046 (https://llvm.org/bugs/show_bug.cgi?id=27046).
The PPCInstrInfo::optimizeCompareInstr function could create a new use of
CR0, even if CR0 were previously dead. This patch marks CR0 live if a use of
CR0 is created.
Author: Tom Jablin (tjablin)
Reviewers: hfinkel kbarton cycheng
http://reviews.llvm.org/D18884
llvm-svn: 266040
In the ELFv2 ABI, we are not required to save all CR fields. If only one
nonvolatile CR field is clobbered, use mfocrf instead of mfcr to
selectively save the field, because mfocrf has short latency compares to
mfcr.
Thanks Nemanja's invaluable hint!
Reviewers: nemanjai tjablin hfinkel kbarton
http://reviews.llvm.org/D17749
llvm-svn: 266038
In Memcpy lowering we had missed a dependence from the load of the
operation to successor operations. This causes us to potentially
construct an in initial DAG with a memory dependence not fully
represented in the chain sub-DAG but rather require looking at the
entire DAG breaking alias analysis by allowing incorrect repositioning
of memory operations.
To work around this, r200033 changed DAGCombiner::GatherAllAliases to be
conservative if any possible issues to happen. Unfortunately this check
forbade many non-problematic situations as well. For example, it's
common for incoming argument lowering to add a non-aliasing load hanging
off of EntryNode. Then, if GatherAllAliases visited EntryNode, it would
find that other (unvisited) use of the EntryNode chain, and just give up
entirely. Furthermore, the check was incomplete: it would not actually
detect all such potentially problematic DAG constructions, because
GatherAllAliases did not guarantee to visit all chain nodes going up to
the root EntryNode. This is in general fine -- giving up early will just
miss a potential optimization, not generate incorrect results. But, for
this non-chain dependency detection code, it's possible that you could
have a load attached to a higher-up chain node than any which were
visited. If that load aliases your store, but the only dependency is
through the value operand of a non-aliasing store, it would've been
missed by this code, and potentially reordered.
With the dependence added, this check can be removed and Alias Analysis
can be much more aggressive. This fixes code quality regression in the
Consecutive Store Merge cleanup (D14834).
Test Change:
ppc64-align-long-double.ll now may see multiple serializations
of its stores
Differential Revision: http://reviews.llvm.org/D18062
llvm-svn: 265836
This is the same change on PPC64 as r255821 on AArch64. I have even borrowed
his commit message.
The access function has a short entry and a short exit, the initialization
block is only run the first time. To improve the performance, we want to
have a short frame at the entry and exit.
We explicitly handle most of the CSRs via copies. Only the CSRs that are not
handled via copies will be in CSR_SaveList.
Frame lowering and prologue/epilogue insertion will generate a short frame
in the entry and exit according to CSR_SaveList. The majority of the CSRs will
be handled by register allcoator. Register allocator will try to spill and
reload them in the initialization block.
We add CSRsViaCopy, it will be explicitly handled during lowering.
1> we first set FunctionLoweringInfo->SplitCSR if conditions are met (the target
supports it for the given machine function and the function has only return
exits). We also call TLI->initializeSplitCSR to perform initialization.
2> we call TLI->insertCopiesSplitCSR to insert copies from CSRsViaCopy to
virtual registers at beginning of the entry block and copies from virtual
registers to CSRsViaCopy at beginning of the exit blocks.
3> we also need to make sure the explicit copies will not be eliminated.
Author: Tom Jablin (tjablin)
Reviewers: hfinkel kbarton cycheng
http://reviews.llvm.org/D17533
llvm-svn: 265781
Summary:
EHPad BB are not entered the classic way and therefor do not need to be placed after their predecessors. This patch make sure EHPad BB are not chosen amongst successors to form chains, and are selected as last resort when selecting the best candidate.
EHPad are scheduled in reverse probability order in order to have them flow into each others naturally.
Reviewers: chandlerc, majnemer, rafael, MatzeB, escha, silvas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D17625
llvm-svn: 265726
http://reviews.llvm.org/D18562
A large number of testcases has been modified so they pass after this test.
One testcase is deleted, because I realized even after undoing the original
change that was committed with this testcase, the testcase still passes. So
I removed it. The change to one other testcase (test/CodeGen/PowerPC/pr25802.ll)
is an arbitrary change to keep it passing. Given the original intention of the
testcase, and the fact that fixing it will require some time to change the testcase,
we concluded that this quick change will be enough.
llvm-svn: 265683
http://reviews.llvm.org/D18405
When the integer value loaded is never used directly as integer we should use VSX
or Floating Point Facility integer loads and avoid extra direct move
llvm-svn: 265593
This patch enable sibling call optimization on ppc64 ELFv1/ELFv2 abi, and
add a couple of test cases. This patch also passed llvm/clang bootstrap
test, and spec2006 build/run/result validation.
Original issue: https://llvm.org/bugs/show_bug.cgi?id=25617
Great thanks to Tom's (tjablin) help, he contributed a lot to this patch.
Thanks Hal and Kit's invaluable opinions!
Reviewers: hfinkel kbarton
http://reviews.llvm.org/D16315
llvm-svn: 265506
We missed a handful of .mir tests that existed outside the
test/CodeGen/MIR directory.
Also fix the three powerpc .mir tests that nobody noticed were broken.
llvm-svn: 265350
Previously, HandleLastUse would delete RegRef information for sub-registers
if they were dead even if their corresponding super-register were still live.
If the super-register were later renamed, then the definitions of the
sub-register would not be updated appropriately. This patch alters the
behavior so that RegInfo information for sub-registers is only deleted when
the sub-register and super-register are both dead.
This resolves PR26775. This is the mirror image of Hal's r227311 commit.
Author: Tom Jablin (tjablin)
Reviewers: kbarton uweigand nemanjai hfinkel
http://reviews.llvm.org/D18448
llvm-svn: 265097
This mostly cosmetic patch moves the DebugEmissionKind enum from DIBuilder
into DICompileUnit. DIBuilder is not the right place for this enum to live
in — a metadata consumer should not have to include DIBuilder.h.
I also added a Verifier check that checks that the emission kind of a
DICompileUnit is actually legal.
http://reviews.llvm.org/D18612
<rdar://problem/25427165>
llvm-svn: 265077
Chapter 3 of the QPX manual states that, "Scalar floating-point load
instructions, defined in the Power ISA, cause a replication of the source data
across all elements of the target register." Thus, if we have a load followed
by a QPX splat (from the first lane), the splat is redundant. This adds a late
MI-level pass to remove the redundant splats in some of these cases
(specifically when both occur in the same basic block).
This optimization is scheduled just prior to post-RA scheduling. It can't happen
before anything that might replace the load with some already-computed quantity
(i.e. store-to-load forwarding).
llvm-svn: 265047
The test case added in r265023 is failing on ninja-x64-msvc-RA-centos6.
Update the test to make less specific assumptions on code generation.
llvm-svn: 265026
PPCSimplifyAddress contains this code:
IntegerType *OffsetTy = ((VT == MVT::i32) ? Type::getInt32Ty(*Context)
: Type::getInt64Ty(*Context));
to determine the type to be used for an index register, if one needs
to be created. However, the "VT" here is the type of the data being
loaded or stored, *not* the type of an address. This means that if
a data element of type i32 is accessed using an index that does not
not fit into 32 bits, a wrong address is computed here.
Note that PPCFastISel is only ever used on 64-bit currently, so the type
of an address is actually *always* MVT::i64. Other parts of the code,
even in this same PPCSimplifyAddress routine, already rely on that fact.
Thus, this patch changes the code to simply unconditionally use
Type::getInt64Ty(*Context) as OffsetTy.
llvm-svn: 265023
The fast isel pass currently emits a COPY_TO_REGCLASS node to convert
from a F4RC to a F8RC register class during conversion of a
floating-point number to integer. There is actually no support in the
common code instruction printers to emit COPY_TO_REGCLASS nodes, so the
PowerPC back-end has special code there to simply ignore
COPY_TO_REGCLASS.
This is correct *if and only if* the source and destination registers of
COPY_TO_REGCLASS are the same (except for the different register class).
But nothing guarantees this to be the case, and if the register
allocator does end up allocating source and destination to different
registers after all, the back-end simply generates incorrect code. I've
included a test case that shows such incorrect code generation.
However, it seems that COPY_TO_REGCLASS is actually not intended to be
used at the MI layer at all. It is used during SelectionDAG, but always
lowered to a plain COPY before emitting MI. Other back-end's fast isel
passes never emit COPY_TO_REGCLASS at all. I suspect it is simply wrong
for the PowerPC back-end to emit it here.
This patch changes the PowerPC back-end to directly emit COPY instead of
COPY_TO_REGCLASS and removes the special handling in the instruction
printers.
Differential Revision: http://reviews.llvm.org/D18605
llvm-svn: 265020
When dealing with complex<float>, and similar structures with two
single-precision floating-point numbers, especially when such things are being
passed around by value, we'll sometimes end up loading both float values by
extracting them from one 64-bit integer load. It looks like this:
t13: i64,ch = load<LD8[%ref.tmp]> t0, t6, undef:i64
t16: i64 = srl t13, Constant:i32<32>
t17: i32 = truncate t16
t18: f32 = bitcast t17
t19: i32 = truncate t13
t20: f32 = bitcast t19
The problem, especially before the P8 where those bitcasts aren't legal (and
get expanded via the stack), is that it would have been better to use two
floating-point loads directly. Here we add a target-specific DAGCombine to do
just that. In short, we turn:
ld 3, 0(5)
stw 3, -8(1)
rldicl 3, 3, 32, 32
stw 3, -4(1)
lfs 3, -4(1)
lfs 0, -8(1)
into:
lfs 3, 4(5)
lfs 0, 0(5)
llvm-svn: 264988
Instead of using two feature bits, one to indicate the availability of the
popcnt[dw] instructions, and another to indicate whether or not they're fast,
use a single enum. This allows more consistent control via target attribute
strings, and via Clang's command line.
llvm-svn: 264690
Minimum density for both optsize and non optsize are now options
-sparse-jump-table-density (default 10) for non optsize functions
-dense-jump-table-density (default 40) for optsize functions, which
matches the current default. This improves several benchmarks at google
at the cost of a small codesize increase. For code compiled with -Os,
the old behavior continues
llvm-svn: 264689
The A2 cores support the popcntw/popcntd instructions, but they're microcoded,
and slower than our default software emulation. Specifically, popcnt[dw] take
approximately 74 cycles, whereas our software emulation takes only 24-28
cycles.
I've added a new target feature to indicate a slow popcnt[dw], instead of just
removing the existing target feature from the a2/a2q processor models, because:
1. This allows us to return more accurate information via the TTI interface
(I recognize that this currently makes no practical difference)
2. Is hopefully easier to understand (it allows the core's features to match
its manual while still having the desired effect).
llvm-svn: 264600
Intrinsic::maxnum and Intrinsic::minnum, along with the associated libc
function calls (fmax[f], etc.) generally map to function calls after lowering.
For some vector types with QPX at least, however, we can legally lower these,
and we don't need to prohibit CTR-based loops on their account.
It turned out, however, that the logic that checked the opcodes associated with
intrinsics was broken (it would set the Opcode variable, but that variable was
later checked only if set for some otherwise-external function call.
This fixes the latter problem and adds the FMAX/MINNUM mappings.
llvm-svn: 264532
This patch corresponds to review:
http://reviews.llvm.org/D17711
It disables direct moves on these operations in 32-bit mode since the patterns
assume 64-bit registers. The final patch is slightly different from the
Phabricator review as the bitcast operations needed to be disabled in 32-bit
mode as well. This fixes PR26617.
llvm-svn: 264282
For fcmp, major concern about the following 6 cases is NaN result. The
comparison result consists of 4 bits, indicating lt, eq, gt and un (unordered),
only one of which will be set. The result is generated by fcmpu
instruction. However, bc instruction only inspects one of the first 3
bits, so when un is set, bc instruction may jump to to an undesired
place.
More specifically, if we expect an unordered comparison and un is set, we
expect to always go to true branch; in such case UEQ, UGT and ULT still
give false, which are undesired; but UNE, UGE, ULE happen to give true,
since they are tested by inspecting !eq, !lt, !gt, respectively.
Similarly, for ordered comparison, when un is set, we always expect the
result to be false. In such case OGT, OLT and OEQ is good, since they are
actually testing GT, LT, and EQ respectively, which are false. OGE, OLE
and ONE are tested through !lt, !gt and !eq, and these are true.
llvm-svn: 263753
This patch prevents CTR loops optimization when using soft float operations
inside loop body. Soft float operations use function calls, but function
calls are not allowed inside CTR optimized loops.
Patch by Aleksandar Beserminji.
Differential Revision: http://reviews.llvm.org/D17600
llvm-svn: 263727
This patch corresponds to review:
http://reviews.llvm.org/D17712
We were not clearing the TOC vector in PPCAsmPrinter when initializing it. This
caused duplicate definition asserts when the pass is reused on the module
(i.e. with -compile-twice or in JIT contexts).
llvm-svn: 263338
Corresponds to Phabricator review:
http://reviews.llvm.org/D16592
This fix includes both an update to how we handle the "generic" CPU on LE
systems as well as Anton's fix for the Fast Isel issue.
llvm-svn: 262233
Currently we always expand ISD::FNEG. For v4f32 and v2f64 vector types VSX has
native support for this opcode
Phabricator: http://reviews.llvm.org/D17647
llvm-svn: 262079
This is what was meant to be in the initial commit to fix this bug. The
parens were missing. This commit also adds a test case for the bug and
has undergone full testing on PPC and X86.
llvm-svn: 261546
Summary:
Without this, this command
$ llvm-run llc -stop-after machine-cp -o - <( echo '' )
outputs an error, because we close stdout twice -- once when closing the
file opened for "-o", and again when closing outs().
Also clarify in the outs() definition that you can't ever call it if you
want to open your own raw_fd_ostream on stdout.
Reviewers: jroelofs, tstellarAMD
Subscribers: jholewinski, qcolombet, dsanders, llvm-commits
Differential Revision: http://reviews.llvm.org/D17422
llvm-svn: 261286
Using the load immediate only when the immediate (whether signed or unsigned)
can fit in a 16-bit signed field. Namely, from -32768 to 32767 for signed and
0 to 65535 for unsigned. This patch also ensures that we sign-extend under the
right conditions.
llvm-svn: 259840
This patch consists of two parts: a performance fix in DAGCombiner.cpp
and a correctness fix in SelectionDAG.cpp.
The test case tests the bug that's uncovered by the performance fix, and
fixed by the correctness fix.
The performance fix keeps the containers required by the
hasPredecessorHelper (which is a lazy DFS) and reuse them. Since
hasPredecessorHelper is called in a loop, the overall efficiency reduced
from O(n^2) to O(n), where n is the number of SDNodes.
The correctness fix keeps iterating the neighbor list even if it's time
to early return. It will return after finishing adding all neighbors to
Worklist, so that no neighbors are discarded due to the original early
return.
llvm-svn: 259691
Recommited, after some fixing with test cases.
Updated test cases:
test/CodeGen/AArch64/arm64-misched-memdep-bug.ll
test/CodeGen/AArch64/tailcall_misched_graph.ll
Temporarily disabled test cases:
test/CodeGen/AMDGPU/split-vector-memoperand-offsets.ll
test/CodeGen/PowerPC/ppc64-fastcc.ll (partially updated)
test/CodeGen/PowerPC/vsx-fma-m.ll
test/CodeGen/PowerPC/vsx-fma-sp.ll
http://reviews.llvm.org/D8705
Reviewers: Hal Finkel, Andy Trick.
llvm-svn: 259673
The purpose of PPCVSXFMAMutate is to elide copies by changing FMA forms
on PPC.
%vreg6<def> = COPY %vreg96
%vreg6<def,tied1> = XSMADDASP %vreg6<tied0>, %vreg5<kill>, %vreg7
;v6 = v6 + v5 * v7
is replaced by
%vreg5<def,tied1> = XSMADDMSP %vreg5<tied0>, %vreg7, %vreg96
;v5 = v5 * v7 + v96
This was broken in the case where the target register was also used as a
multiplicand. Fix this case by checking for it and replacing both uses
with the copied register.
%vreg6<def> = COPY %vreg96
%vreg6<def,tied1> = XSMADDASP %vreg6<tied0>, %vreg5<kill>, %vreg6
;v6 = v6 + v5 * v6
is replaced by
%vreg5<def,tied1> = XSMADDMSP %vreg5<tied0>, %vreg96, %vreg96
;v5 = v5 * v96 + v96
llvm-svn: 259617
check that the sign extended constant fits into 16-bits if we want a
zero extended value, otherwise go ahead and put it together piecemeal.
Fixes PR26356.
llvm-svn: 259177
For historic reasons, the behavior of .align differs between targets.
Fortunately, there are alternatives, .p2align and .balign, which make the
interpretation of the parameter explicit, and which behave consistently across
targets.
This patch teaches MC to use .p2align instead of .align, so that people reading
code for multiple architectures don't have to remember which way each platform
does its .align directive.
Differential Revision: http://reviews.llvm.org/D16549
llvm-svn: 258750
Chuang-Yu Cheng