Summary:
This patch adds the following
1. Adds a skeleton scheduler model for AMD Znver1.
2. Introduces the znver1 execution units and pipes.
3. Caters the instructions based on the generic scheduler classes.
4. Further additions to the scheduler model with instruction itineraries will be carried out incrementally based on
a. Instructions types
b. Registers used
5. Since itineraries are not added based on instructions, throughput information are bound to change when incremental changes are added.
6. Scheduler testcases are modified accordingly to suit the new model.
Patch by Ganesh Gopalasubramanian. With minor formatting tweaks from me.
Reviewers: craig.topper, RKSimon
Subscribers: javed.absar, shivaram, ddibyend, vprasad
Differential Revision: https://reviews.llvm.org/D35293
llvm-svn: 308411
Summary: I believe this should be supported on GLM since RDSEED is.
Reviewers: m_zuckerman, zvi, RKSimon
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34828
llvm-svn: 307060
AVX512_VPOPCNTDQ is a new feature set that was published by Intel.
The patch represents the LLVM side of the addition of two new intrinsic based instructions (vpopcntd and vpopcntq).
Differential Revision: https://reviews.llvm.org/D33169
llvm-svn: 303858
According to Intel's Optimization Reference Manual for SNB+:
" For LEA instructions with three source operands and some specific situations, instruction latency has increased to 3 cycles, and must
dispatch via port 1:
- LEA that has all three source operands: base, index, and offset
- LEA that uses base and index registers where the base is EBP, RBP,or R13
- LEA that uses RIP relative addressing mode
- LEA that uses 16-bit addressing mode "
This patch currently handles the first 2 cases only.
Differential Revision: https://reviews.llvm.org/D32277
llvm-svn: 303333
According to Intel's Optimization Reference Manual for SNB+:
" For LEA instructions with three source operands and some specific situations, instruction latency has increased to 3 cycles, and must
dispatch via port 1:
- LEA that has all three source operands: base, index, and offset
- LEA that uses base and index registers where the base is EBP, RBP,or R13
- LEA that uses RIP relative addressing mode
- LEA that uses 16-bit addressing mode "
This patch currently handles the first 2 cases only.
Differential Revision: https://reviews.llvm.org/D32277
llvm-svn: 303183
This patch adds support for the the LightWeight Profiling (LWP) instructions which are available on all AMD Bulldozer class CPUs (bdver1 to bdver4).
Reapplied - this time without changing line endings of existing files.
Differential Revision: https://reviews.llvm.org/D32769
llvm-svn: 302041
This patch adds support for the the LightWeight Profiling (LWP) instructions which are available on all AMD Bulldozer class CPUs (bdver1 to bdver4).
Differential Revision: https://reviews.llvm.org/D32769
llvm-svn: 302028
when the subtarget has fast strings.
This has two advantages:
- Speed is improved. For example, on Haswell thoughput improvements increase
linearly with size from 256 to 512 bytes, after which they plateau:
(e.g. 1% for 260 bytes, 25% for 400 bytes, 40% for 508 bytes).
- Code is much smaller (no need to handle boundaries).
llvm-svn: 300957
VZEROUPPER should not be issued on Knights Landing (KNL), but on Skylake-avx512 it should be.
Differential Revision: https://reviews.llvm.org/D29874
llvm-svn: 296859
Summary:
Sandy Bridge and later CPUs have better throughput using a SHLD to implement rotate versus the normal rotate instructions. Additionally it saves one uop and avoids a partial flag update dependency.
This patch implements this change on any Sandy Bridge or later processor without BMI2 instructions. With BMI2 we will use RORX as we currently do.
Reviewers: zvi
Reviewed By: zvi
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D30181
llvm-svn: 295697
We only implemented it for one of the 3 HLE instructions and that instruction is also under the RTM flag. Clang only implements the RTM flag from its command line.
llvm-svn: 294562
This patch does the following.
1. Adds an Intrinsic int_x86_clzero which works with __builtin_ia32_clzero
2. Identifies clzero feature using cpuid info. (Function:8000_0008, Checks if EBX[0]=1)
3. Adds the clzero feature under znver1 architecture.
4. The custom inserter is added in Lowering.
5. A testcase is added to check the intrinsic.
6. The clzero instruction is added to assembler test.
Patch by Ganesh Gopalasubramanian with a couple formatting tweaks, a disassembler test, and using update_llc_test.py from me.
Differential revision: https://reviews.llvm.org/D29385
llvm-svn: 294558
64-bit integer division in Intel CPUs is extremely slow, much slower
than 32-bit division. On the other hand, 8-bit and 16-bit divisions
aren't any faster. The only important exception is Atom where DIV8
is fastest. Because of that, the patch
1) Enables bypassing of 64-bit division for Atom, Silvermont and
all big cores.
2) Modifies 64-bit bypassing to use 32-bit division instead of
16-bit one. This doesn't make the shorter division slower but
increases chances of taking it. Moreover, it's much more likely
to prove at compile-time that a value fits 32 bits and doesn't
require a run-time check (e.g. zext i32 to i64).
Differential Revision: https://reviews.llvm.org/D28196
llvm-svn: 291800
Summary:
This patch enables the following
1. AMD family 17h architecture using "znver1" tune flag (-march, -mcpu).
2. ISAs that are enabled for "znver1" architecture.
3. Checks ADX isa from cpuid to identify "znver1" flag when -march=native is used.
4. ISAs FMA4, XOP are disabled as they are dropped from amdfam17.
5. For the time being, it uses the btver2 scheduler model.
6. Test file is updated to check this flag.
This item is linked to clang review item https://reviews.llvm.org/D28018
Patch by Ganesh Gopalasubramanian
Reviewers: RKSimon, craig.topper
Subscribers: vprasad, RKSimon, ashutosh.nema, llvm-commits
Differential Revision: https://reviews.llvm.org/D28017
llvm-svn: 291543
Summary:
Prefer expansions such as: pmullw,pmulhw,unpacklwd,unpackhwd over pmulld.
On Silvermont [source: Optimization Reference Manual]:
PMULLD has a throughput of 1/11 [instruction/cycles].
PMULHUW/PMULHW/PMULLW have a throughput of 1/2 [instruction/cycles].
Fixes pr31202.
Analysis of this issue was done by Fahana Aleen.
Reviewers: wmi, delena, mkuper
Subscribers: RKSimon, llvm-commits
Differential Revision: https://reviews.llvm.org/D27203
llvm-svn: 288844
Summary:
This is needed to make the v64i8 and v32i16 types legal for the 512-bit VBMI instructions. Fixes PR30912.
Reviewers: delena, zvi
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D26322
llvm-svn: 286339
This change adds transformations such as:
zext(or(setcc(eq, (cmp x, 0)), setcc(eq, (cmp y, 0))))
To:
srl(or(ctlz(x), ctlz(y)), log2(bitsize(x))
This optimisation is beneficial on Jaguar architecture only, where lzcnt has a good reciprocal throughput.
Other architectures such as Intel's Haswell/Broadwell or AMD's Bulldozer/PileDriver do not benefit from it.
For this reason the change also adds a "HasFastLZCNT" feature which gets enabled for Jaguar.
Differential Revision: https://reviews.llvm.org/D23446
llvm-svn: 284248
On modern Intel processors hardware SQRT in many cases is faster than RSQRT
followed by Newton-Raphson refinement. The patch introduces a simple heuristic
to choose between hardware SQRT instruction and Newton-Raphson software
estimation.
The patch treats scalars and vectors differently. The heuristic is that for
scalars the compiler should optimize for latency while for vectors it should
optimize for throughput. It is based on the assumption that throughput bound
code is likely to be vectorized.
Basically, the patch disables scalar NR for big cores and disables NR completely
for Skylake. Firstly, scalar SQRT has shorter latency than NR code in big cores.
Secondly, vector SQRT has been greatly improved in Skylake and has better
throughput compared to NR.
Differential Revision: https://reviews.llvm.org/D21379
llvm-svn: 277725
Summary:
MONITORX/MWAITX instructions provide similar capability to the MONITOR/MWAIT
pair while adding a timer function, such that another termination of the MWAITX
instruction occurs when the timer expires. The presence of the MONITORX and
MWAITX instructions is indicated by CPUID 8000_0001, ECX, bit 29.
The MONITORX and MWAITX instructions are intercepted by the same bits that
intercept MONITOR and MWAIT. MONITORX instruction establishes a range to be
monitored. MWAITX instruction causes the processor to stop instruction execution
and enter an implementation-dependent optimized state until occurrence of a
class of events.
Opcode of MONITORX instruction is "0F 01 FA". Opcode of MWAITX instruction is
"0F 01 FB". These opcode information is used in adding tests for the
disassembler.
These instructions are enabled for AMD's bdver4 architecture.
Patch by Ganesh Gopalasubramanian!
Reviewers: echristo, craig.topper, RKSimon
Subscribers: RKSimon, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D19795
llvm-svn: 269911
For compilations with no explicit cpu specified, this exhibits
nice gains on Silvermont, with neutral performance on big cores.
Differential Revision: http://reviews.llvm.org/D19138
llvm-svn: 267809
btver1 is a SSSE3/SSE4a only CPU - it doesn't have AVX and doesn't support XSAVE.
Differential Revision: http://reviews.llvm.org/D17683
llvm-svn: 262782
Summary:
- Rename `"skylake"` == SkylakeServerProc to `"skylake-avx512"`
- Change `"skylake"` to denote SkylakeClientProc
- Fix the detection of cpu family 6 and model 94 to be
SkylakeClientProc instead of SkylakeServerProc
- Remove the `"cnl"` for CannonLake
Reviewers: craig.topper, delena
Subscribers: zansari, echristo, qcolombet, RKSimon, spatel, DavidKreitzer, mcrosier, llvm-commits
Differential Revision: http://reviews.llvm.org/D17090
llvm-svn: 261482
Changes in X86.td:
I set features of Intel processors in incremental form: IVB = SNB + X HSW = IVB + X ..
I added Skylake client processor and defined it's features
FeatureADX was missing on KNL
Added some new features to appropriate processors SMAP, IFMA, PREFETCHWT1, VMFUNC and others
Differential Revision: http://reviews.llvm.org/D16357
llvm-svn: 258659
The feature flag is for VPERMB,VPERMI2B,VPERMT2B and VPMULTISHIFTQB instructions.
More about the instruction can be found in:
hattps://software.intel.com/sites/default/files/managed/07/b7/319433-023.pdf
Differential Revision: http://reviews.llvm.org/D16190
llvm-svn: 258012
the feature flag is essential for RDPKRU and WRPKRU instruction
more about the instruction can be found in the SDM rev 56, vol 2 from http://www.intel.com/sdm
Differential Revision: http://reviews.llvm.org/D15491
llvm-svn: 255644
These instructions are not supported by all CPUs in 64-bit mode. Emitting them
causes Chromium to crash on start-up for users with such chips.
(GCC puts these instructions behind -msahf on 64-bit for the same reason.)
This patch adds FeatureLAHFSAHF, enables it by default for 32-bit targets
and modern CPUs, and changes X86InstrInfo::copyPhysReg back to the lowering
from before r244503 when the instructions are not available.
Differential Revision: http://reviews.llvm.org/D15240
llvm-svn: 254793
Craig Topper