In file PPCBranchSelector.cpp we tend to over estimate code size due to large
alignment and inline assembly. Usually it causes larger computed branch offset,
it is not big problem. But sometimes it may also causes smaller computed branch
offset than actual branch offset. If the offset is close to the limit of
encoding, it may cause problem at run time.
Following is a simplified example.
actual estimated
address address
...
bne Far 100 10c
.p2align 4
Near: 110 110
...
Far: 8108 8108
Actual offset: 0x8108 - 0x100 = 0x8008
Computed offset: 0x8108 - 0x10c = 0x7ffc
The computed offset is at most ((1 << alignment) - 4) bytes smaller than actual
offset. So we add this number to the offset for safety.
Differential Revision: https://reviews.llvm.org/D57718
llvm-svn: 355529
Move the stdu instruction in the prologue and epilogue.
This should provide a small performance boost in functions that are able to do
this. I've kept this change rather conservative at the moment and functions
with frame pointers or base pointers will not try to move the stack pointer
update.
Differential Revision: https://reviews.llvm.org/D42590
llvm-svn: 355085
Summary:
Turns out the test was not correct, I had to adjust the test to work. I
also added CHECK-LABELs for better error messages from FileCheck while
I'm here.
Reviewers: jsji
Subscribers: nemanjai, eraman, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58614
llvm-svn: 355079
Summary:
Fast selection of llvm fptoi & fptrunc instructions is not handled well about
VSX instruction support.
We'd use VSX float convert integer instruction instead of non-vsx float convert
integer instruction if the operand register class is VSSRC or VSFRC because i32
and i64 are mapped to VSSRC and VSFRC correspondingly if VSX feature is
openeded.
For float trunc instruction, we do this silimar work like float convert integer
instruction to try to use VSX instruction.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D58430
llvm-svn: 354762
Added four test files to check the existing behaviour of prologue
and epilogue code generation. This patch was done as a setup for
the upcoming patch listed on Phabricator that will change how the
prologue and epilogue work.
The upcoming patch is: https://reviews.llvm.org/D42590
llvm-svn: 353994
If we're comparing some value for equality against 2 constants
and those constants have an absolute difference of just 1 bit,
then we can offset and mask off that 1 bit and reduce to a single
compare against zero:
and/or (setcc X, C0, ne), (setcc X, C1, ne/eq) -->
setcc ((add X, -C1), ~(C0 - C1)), 0, ne/eq
https://rise4fun.com/Alive/XslKj
This transform is disabled by default using a TLI hook
("convertSetCCLogicToBitwiseLogic()").
That should be overridden for AArch64, MIPS, Sparc and possibly
others based on the asm shown in:
https://bugs.llvm.org/show_bug.cgi?id=40611
llvm-svn: 353859
The PowerPC code generator currently scalarizes vector truncates that would fit in a vector register, resulting in vector extracts, scalar operations, and vector merges. This patch custom lowers a vector truncate that would fit in a register to a vector shuffle instead.
Differential Revision: https://reviews.llvm.org/D56507
llvm-svn: 353724
The sqrt case is faster and we already do this for the case where
the exponent is 0.25. This adds the 0.75 case which is also not
sensitive to signed zeros.
Patch by Whitney Tsang (Whitney)
Differential revision: https://reviews.llvm.org/D57434
llvm-svn: 353557
I noticed that we are missing this canonicalization in IR:
rL352515
...and then realized that we don't get this right in SDAG either,
so this has to be fixed first regardless of what we choose to do in IR.
The existing fold was limited to scalars and using the wrong predicate
to guard the transform. We have a boolean contents TLI query that can
be used to decide which direction to fold.
This may eventually lead back to the problems/question in:
https://bugs.llvm.org/show_bug.cgi?id=40486
...but it makes no difference to that yet.
Differential Revision: https://reviews.llvm.org/D57401
llvm-svn: 353433
Summary:
Experimentally we found that promotion to scalars carries less benefits
than sinking and hoisting in LICM. When using MemorySSA, we build an
AliasSetTracker on demand in order to reuse the current infrastructure.
We only build it if less than AccessCapForMSSAPromotion exist in the
loop, a cap that is by default set to 250. This value ensures there are
no runtime regressions, and there are small compile time gains for
pathological cases. A much lower value (20) was found to yield a single
regression in the llvm-test-suite and much higher benefits for compile
times. Conservatively we set the current cap to a high value, but we will
explore lowering it when MemorySSA is enabled by default.
Reviewers: sanjoy, chandlerc
Subscribers: nemanjai, jlebar, Prazek, george.burgess.iv, jfb, jsji, llvm-commits
Differential Revision: https://reviews.llvm.org/D56625
llvm-svn: 353339
There are 2 changes visible here:
1. There's no reason to limit this transform based on number
of condition registers. That diff allows PPC to produce
slightly better (dot-instructions should be generally good)
code.
Note: someone that cares about PPC codegen might want to
look closer at that output because it seems like we could
still improve this.
2. We (probably?) should not bother trying to form uaddo (or
other overflow ops) when there's no target support for such
an op. This goes beyond checking whether the op is expanded
because both PPC and AArch64 show better codegen for standard
types regardless of whether the op is legal/custom.
llvm-svn: 353001
This fixes most references to the paths:
llvm.org/svn/
llvm.org/git/
llvm.org/viewvc/
github.com/llvm-mirror/
github.com/llvm-project/
reviews.llvm.org/diffusion/
to instead point to https://github.com/llvm/llvm-project.
This is *not* a trivial substitution, because additionally, all the
checkout instructions had to be migrated to instruct users on how to
use the monorepo layout, setting LLVM_ENABLE_PROJECTS instead of
checking out various projects into various subdirectories.
I've attempted to not change any scripts here, only documentation. The
scripts will have to be addressed separately.
Additionally, I've deleted one document which appeared to be outdated
and unneeded:
lldb/docs/building-with-debug-llvm.txt
Differential Revision: https://reviews.llvm.org/D57330
llvm-svn: 352514
If bottom of block BB has only one successor OldTop, in most cases it is profitable to move it before OldTop, except the following case:
-->OldTop<-
| . |
| . |
| . |
---Pred |
| |
BB-----
Move BB before OldTop can't reduce the number of taken branches, this patch detects this case and prevent the moving.
Differential Revision: https://reviews.llvm.org/D57067
llvm-svn: 352236
Fast selection of llvm icmp and fcmp instructions is not handled well about VSX instruction support.
We'd use VSX float comparison instruction instead of non-vsx float comparison instruction
if the operand register class is VSSRC or VSFRC because i32 and i64 are mapped to VSSRC and
VSFRC correspondingly if VSX feature is opened.
If the target does not have corresponding VSX instruction comparison for some type,
just copy VSX-related register to common float register class and use non-vsx comparison instruction.
Differential Revision: https://reviews.llvm.org/D57078
llvm-svn: 352174
This patch exploits the instructions that store a single element from a vector
to preform a (store (extract_elt)). We already have code that does this with
ISA 3.0 instructions that were added to handle i8/i16 types. However, we had
never exploited the existing ones that handle f32/f64/i32/i64 types.
Differential revision: https://reviews.llvm.org/D56175
llvm-svn: 352131
compiler identification lines in test-cases.
(Doing so only because it's then easier to search for references which
are actually important and need fixing.)
llvm-svn: 351200
Part of the effort to refactoring frame pointer code generation. We used
to use two function attributes "no-frame-pointer-elim" and
"no-frame-pointer-elim-non-leaf" to represent three kinds of frame
pointer usage: (all) frames use frame pointer, (non-leaf) frames use
frame pointer, (none) frame use frame pointer. This CL makes the idea
explicit by using only one enum function attribute "frame-pointer"
Option "-frame-pointer=" replaces "-disable-fp-elim" for tools such as
llc.
"no-frame-pointer-elim" and "no-frame-pointer-elim-non-leaf" are still
supported for easy migration to "frame-pointer".
tests are mostly updated with
// replace command line args ‘-disable-fp-elim=false’ with ‘-frame-pointer=none’
grep -iIrnl '\-disable-fp-elim=false' * | xargs sed -i '' -e "s/-disable-fp-elim=false/-frame-pointer=none/g"
// replace command line args ‘-disable-fp-elim’ with ‘-frame-pointer=all’
grep -iIrnl '\-disable-fp-elim' * | xargs sed -i '' -e "s/-disable-fp-elim/-frame-pointer=all/g"
Patch by Yuanfang Chen (tabloid.adroit)!
Differential Revision: https://reviews.llvm.org/D56351
llvm-svn: 351049
Bad machine code: Illegal virtual register for instruction
function: TestULE
basic block: %bb.0 entry (0x1000a39b158)
instruction: %2:crrc = FCMPUD %1:vsfrc, %3:f8rc
operand 1: %1:vsfrc
Fix assert about missing match between fcmp instruction and register class.
We should use vsx related cmp instruction xvcmpudp instead of fcmpu when vsx is opened.
add -verifymachineinstrs option into related test cases to enable the verify pass.
Differential Revision: https://reviews.llvm.org/D55686
llvm-svn: 350685
When switched to the MI scheduler for P9, the hardware is modeled as out of order.
However, inside the MI Scheduler algorithm, we still use the in-order scheduling model
as the MicroOpBufferSize isn't set. The MI scheduler take it as the hw cannot buffer
the op. So, only when all the available instructions issued, the pending instruction
could be scheduled. That is not true for our P9 hw in fact.
This patch is trying to enable the Out-of-Order scheduling model. The buffer size 44 is
picked from the P9 hw spec, and the perf test indicate that, its value won't hurt the cpu2017.
With this patch, there are 3 specs improved over 3% and 1 spec deg over 3%. The detail is as follows:
x264_r: +6.95%
cactuBSSN_r: +6.94%
lbm_r: +4.11%
xz_r: -3.85%
And the GEOMEAN for all the C/C++ spec in spec2017 is about 0.18% improved.
Reviewer: Nemanjai
Differential Revision: https://reviews.llvm.org/D55810
llvm-svn: 350285
If x has multiple sign bits than it doesn't matter which one we extend from so we can sext from x's msb instead.
The X86 setcc-combine.ll changes are a little weird. It appears we ended up with a (sext_inreg (aext (trunc (extractelt)))) after type legalization. The sext_inreg+aext now gets optimized by this combine to leave (sext (trunc (extractelt))). Then we visit the trunc before we visit the sext. This ends up changing the truncate to an extractvectorelt from a bitcasted vector. I have a follow up patch to fix this.
Differential Revision: https://reviews.llvm.org/D56156
llvm-svn: 350235
PPCPreEmitPeephole pass.
PPCPreEmitPeephole will convert a BC to B when the conditional branch is
based on a constant CR by CRSET or CRUNSET. This is added in
https://reviews.llvm.org/rL343100.
When the conditional branch is known to be always taken, all branches will
be removed and a new unconditional branch will be inserted. However, when
SeenUse is false the original patch will not remove the branches, but still
insert the new unconditional branch, update the successors and create
inconsistent IR. Compiling the synthetic testcase included can show the
problem we run into.
The patch simply removes the SeenUse condition when adding branches into
InstrsToErase set.
Differential Revision: https://reviews.llvm.org/D56041
llvm-svn: 350223
Summary:
For SDAG, we pretend patchpoints aren't special at all until we emit the code for the pseudo.
Then the verifier runs and it seems like we have a use of an undefined register (the register will
be reserved later, but the verifier doesn't know that).
So this patch call setUsesTOCBasePtr before emit the code for the pseudo, so verifier can know
X2 is a reserved register.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D56148
llvm-svn: 350165
A recent patch has added custom legalization of vector conversions of
v2i16 -> v2f64. This just rounds it out for other types where the input vector
has an illegal (narrower) type than the result vector. Specifically, this will
handle the following conversions:
v2i8 -> v2f64
v4i8 -> v4f32
v4i16 -> v4f32
Differential revision: https://reviews.llvm.org/D54663
llvm-svn: 350155
The current CRBIT spill pseudo-op expansion creates a KILL instruction
that kills the CRBIT and defines the enclosing CR field. However, this
paints a false picture to the register allocator that all bits in the CR
field are killed so copies of other bits out of the field become dead and
removable.
This changes the expansion to preserve the KILL flag on the CRBIT as an
implicit use and to treat the CR field as an undef input.
Thanks to Hal Finkel for the review and Uli Weigand for implementation input.
Differential revision: https://reviews.llvm.org/D55996
llvm-svn: 350153
This is the last one in a series of patches to support better code generation for bitfield insert.
BitPermutationSelector already support ISD::ZERO_EXTEND but not TRUNCATE.
This patch adds support for ISD:TRUNCATE in BitPermutationSelector.
For example of this test case,
struct s64b {
int a:4;
int b:16;
int c:24;
};
void bitfieldinsert64b(struct s64b *p, unsigned char v) {
p->b = v;
}
the selection DAG loos like:
t14: i32,ch = load<(load 4 from %ir.0)> t0, t2, undef:i64
t18: i32 = and t14, Constant:i32<-1048561>
t4: i64,ch = CopyFromReg t0, Register:i64 %1
t22: i64 = AssertZext t4, ValueType:ch:i8
t23: i32 = truncate t22
t16: i32 = shl nuw nsw t23, Constant:i32<4>
t19: i32 = or t18, t16
t20: ch = store<(store 4 into %ir.0)> t14:1, t19, t2, undef:i64
By handling truncate in the BitPermutationSelector, we can use information from AssertZext when selecting t19 and skip the mask operation corresponding to t18.
So the generated sequences with and without this patch are
without this patch
rlwinm 5, 5, 0, 28, 11 # corresponding to t18
rlwimi 5, 4, 4, 20, 27
with this patch
rlwimi 5, 4, 4, 12, 27
Differential Revision: https://reviews.llvm.org/D49076
llvm-svn: 350118
If we are changing the MI operand from Reg to Imm, we need also handle its implicit use if have.
Differential Revision: https://reviews.llvm.org/D56078
llvm-svn: 350115
For atomic value operand which less than 4 bytes need to be masked.
And the related operation to calculate the newvalue can be done in 32 bit gprc.
So just use gprc for mask and value calculation.
Differential Revision: https://reviews.llvm.org/D56077
llvm-svn: 350113
Summary:
This patch is to fix the bug imported by rL341634.
In above submit , the the return type of ISD::ADDE is
14224: SDVTList VTs = DAG.getVTList(MVT::i64, MVT::i64),
but in fact, the second return type of ISD::ADDE should be
MVT::Glue not MVT::i64.
Reviewed By: hfinkel
Differential Revision: https://reviews.llvm.org/D55977
llvm-svn: 350061
Summary:
PowerPC has scalar selects (isel) and vector mask selects (xxsel). But PowerPC
does not have vector CR selects, PowerPC does not support scalar condition
selects on vectors.
In addition to implementing this hook, isSelectSupported() should return false
when the SelectSupportKind is ScalarCondVectorVal, so that predictable selects
are converted into branch sequences.
Reviewed By: steven.zhang, hfinkel
Differential Revision: https://reviews.llvm.org/D55754
llvm-svn: 349727
