工作日誌: 10月 2012

2012年10月30日星期二

x86-to-ARM LnQ Status

Block mode, test inputs

400.perlbench NR
401.bzip2 -- 180 -- S
403.gcc -- 466 -- S
429.mcf -- 53.7 -- S
445.gobmk -- 874 -- S
456.hmmer NR
458.sjeng -- 129 -- S
462.libquantum -- 15.7 -- S
464.h264ref -- 0.0248 RE
471.omnetpp -- 62.1 RE
473.astar -- 126 -- S
483.xalancbmk -- 218 -- S

------------------------------------------------------------------------------------

Summary:

400.perlbench, and 456.hmmer can not run due to floating point precision error
464.h264ref
471.omnetpp

================================================================
Trace Mode, test inputs

400.perlbench NR

401.bzip2 -- 140 -- S

403.gcc -- 335 RE

429.mcf -- 53.5 -- S

445.gobmk -- 533 RE

456.hmmer NR

458.sjeng -- 106 -- S

462.libquantum -- 14.3 -- S

464.h264ref -- 0.0257 RE

471.omnetpp -- 50.3 RE

473.astar -- 104 -- S

483.xalancbmk -- 169 -- S

------------------------------------------------------------------------------------

Summary:

Error inherit from block mode
403.gcc
445.gobmk

===============================================================

guest applications are re-compiled with gcc 4.7 to make sure it really use SSE instructions

Perlbench still stuck in arith.t due to precision problem
bzip OK
gcc: KILLILL, illegal instruction due to incorrect encoding of VST1LNd32

fix alignment encoding for these instructions in getAddrMode6AddressOpValue() in ARMCodeEmitter.cpp

Re-test all but perlbench and hmmer

hang on leslie3d, try to find out why...

trap in infinite loop; maybe due to precision error?
skip it.

Omnetpp: Fail to run; try to find out why...

QEMU cannot run either.

Bwaves: mis-compare; does QEMU get the same result?

Gamess: mis-compare; does QEMU get the same result?

NOTE: unlike bwaves, there are minus signs where it should not appear

Milc: mis-compare;
Zeus: segfault.

Reason: On ARM Linux, the shared library, like ld-2.13.so, libpthread-2.13.so, etc..., are loaded starting at 0x40000000, and and the image of x86 guest starts at 0x08048000. Zeus asks for 0x45efa000 memory for its image, which cannot fit in the ``hole'' between 0x08048000 and 0x40000000.
And I move qemu image to 0x90000000;
So, the guest image is finally put in between 0x40000000 and 0x90000000.
however, during execution, the guest asks more memory, and finally shit happen...

Gromacs: mis-compare
Leslie3d: mis-compare

--------------------------------------------------------------------------------------

Summary:

QEMU FP precision problem

Perlbench and hmmer trap in infinite loop due to FP precision problem
Omnetpp fail to run;
Only cactum and namd success in floating point benchmarks...

9 CINT2006 benchmarks run successfully.
Measure timing...

400.perlbench NR

401.bzip2 -- 163 -- S

403.gcc -- 507 -- S

429.mcf -- 56.1 -- S

445.gobmk -- 955 -- S

456.hmmer NR

458.sjeng -- 126 -- S

462.libquantum -- 16.3 -- S

464.h264ref -- 387 VE

471.omnetpp NR

473.astar -- 114 -- S

483.xalancbmk -- 230 -- S

======================================================================

Trace :

401.bzip2: NOT OK

Infinite loop

403.gcc: mis-compare
429.mcf: OK
445.gobmk: OK
458.sjeng: OK
462.libquantum: OK
473.astar: OK

464.h264ref: NOT OK

*** longjmp causes uninitialized stack frame ***: /home/tk/lnq/install/bin/qemu-i386 terminated
Aborted (core dumped)

483.xalancbmk: NOT OK

Terminate without printing anything

400.perlbench NR

401.bzip2 NR

403.gcc -- 460 VE

429.mcf -- 56.5 -- S

445.gobmk -- 874 -- S

456.hmmer NR

458.sjeng -- 112 -- S

462.libquantum -- 14.7 -- S

464.h264ref NR

471.omnetpp NR

473.astar -- 98.4 -- S

483.xalancbmk NR

===============================================================
Debug Trace Mode:
===============================================================
First, try to find out whose fault, and always use easiest-bug-first strategy to fight.
===============================================================
GCC: Mis-compare

When in trace mode, the blocks are compiled with IFastEnable and Opt::None options. So, check whether this error comes from fast instruction selection mode.

Set optimization options to ``Default'' and disable IFastEnable.

This error is gone.
Confirm!

Now debug becomes simple: run $l gcc two times: enabling and disabling FastISel, and compares logs to locate where went wrong.

FAIL!

Another approach:

EnableFastISel does not affect correctness.
llvm optimization does!

When opt is set to None, gcc got segfault!
When opt is set to Less, gcc runs successfully.

Run block with None, and compare used MI.

Run experiment!

Nothing found!

Still don't know why llvm::CodeGenOpt::None cause fault, try find reduced example.

Run CINT2006 with llvm::CodeGenOpt::None

Wait for result...
Error: 1x401.bzip2 1x403.gcc 1x445.gobmk 1x464.h264ref 1x483.xalancbmk
Success: 1x429.mcf 1x458.sjeng 1x462.libquantum 1x473.astar 1x999.specrand

2012年10月29日星期一

Work log

In target_i386/cpu.h

CPU86_LDouble =:: struct { uint64_t low, uint16_t high; }

Note:

x86 versions of perlbench - arith.t and omnetpp fail to run on ARM with QEMU-0.13 official version but run successfully in QEMU-1.1.1

I tried two compiler : gcc-4.7 and gcc-4.4
The reason is that QEMU does not use CONFIG_SOFTFLOAT for i386 target, even when host is ARM. As a result, QEMU uses only 64-bit double for x86 80-bit floating point registers.
This is strange! I never heard DY report that he fails to run omnetpp, or perlbench.
Others can now run test inputs successfully

Plan to port LnQ to QEMU 1.2 + LLVM 3.2。
Correctness is far important than Performance!!!!!

Work log - ARM NEON Guest Support

[TODO] ARM NEON Guest Support
[TODO] Refine system mode experiment slide
[TODO] Re-implment LnQ
[TODO] Journal paper start

[Q] Blog ?
[Q] Plot tutorial
[Q] x86_64 on ARM64, run user-mode in system mode, ARM64 emulation?

ARM NEON Guest Support:

recompile SPEC with flags: -static -O3 -marm -march=armv7-a -mtune=cortex-a9 -mcpu=cortex-a9 -mfloat-abi=softfp -mfpu=neon -ffast-math -ftree-vectorize -funroll-all-loops -Wl,--whole-archive -lpthread -Wl,--no-whole-archive
GCC configure :

../gcc-linaro-4.7-2012.05/configure --build=i686-build_pc-linux-gnu --host=i686-build_pc-linux-gnu --target=arm-linux-gnueabi --prefix=/home/tk/local/arm-toolchain --enable-languages=c,c++,fortran --with-arch=armv7-a --with-tune=cortex-a8 --with-fpu=neon --with-float=softfp --with-sysroot=/home/tk/local/arm-toolchain/.build/arm-linux-gnueabi/libc --with-pkgversion='crosstool-NG linaro-1.13.1-2012.05-20120523 - Linaro GCC 2012.05' --with-bugurl=https://bugs.launchpad.net/gcc-linaro --enable-__cxa_atexit --enable-libmudflap --enable-libgomp --enable-libssp --with-gmp=/home/tk/local/arm-toolchain/.build --with-mpfr=/home/tk/local/arm-toolchain/.build --with-mpc=/home/tk/local/arm-toolchain/.build --with-ppl=/home/tk/local/arm-toolchain/.build --with-cloog=/home/tk/local/arm-toolchain/.build --enable-cloog-backend=isl --with-libelf=/home/tk/local/arm-toolchain/.build --enable-threads=posix --disable-libstdcxx-pch --enable-linker-build-id --enable-gold --with-local-prefix=/home/tk/local/arm-toolchain/arm-linux-gnueabihf/libc --enable-c99 --enable-long-long --with-mode=arm

'ptrdiff_t' does not name a type: after GCC 4.6, we need to include manually in source files.

don't want to modify source files, add ``#include '' in c++config.h
boring...

when compiling 464.h264, there are error messages: ']' expect: vld4.i32 {d16, d18, d20, d22}, [sp:64] by assembler.

as from binutils 2.19 and 2.21 does not understand this because it use double-space register, which types are double floating point
solution: use 2.23. however, it is now the loader ld has assertion error (WTF!).
don't know how to get rid of this assertion error, I comments out the assertion in bfd/elf32-arm.c:11757
the compiled executable can run successfully on pandaboard

Run native with test inputs

CINT: h264ref verification error
434.zeusmp, 447.dealII, 450.soplex, 459.GemsFDTD, 482.sphinx3 runtime error.

434.zeusmp: over 1G bss (0x45df2c7c bytes), fixed after add 4G swap
447.dealII: segfault; fixed after changing binutils from 2.19 to 2.23
482.sphinx3: program error, program misbehaved.

Summary: all good except 482.sphinx3

2012年10月25日星期四

multi-byte no ops in x86

http://www.asmpedia.org/index.php?title=NOP

90 nop
6690 xchg ax,ax ; 66: switch to 16-bit operand 90: opcode
0f1f00 nop dword ptr [eax] ; 0f1f: 2-byte opcode 00: mod=00 reg=000 rm=000 [EAX]
0f1f4000 nop dword ptr [eax] ; 0f1f: 2-byte opcode 40: mod=01 reg=000 rm=000 [EAX+0x00]
0f1f440000 nop dword ptr [eax+eax] ; 0f1f: 2-byte opcode 44: mod=01 reg=000 rm=100 SIB + 0x00
660f1f440000 nop word ptr [eax+eax] ; 66: switch to 16-bit operand 0f1f: 2-byte opcode 44: mod=01 reg=000 rm=100 SIB + 0x00
0f1f8000000000 nop dword ptr [eax] ; 0f1f: 2-byte opcode 80: mod=10 reg=000 rm=000 [EAX+0x00000000]

2012年10月23日星期二

ARM architecture slides and doc

Lessons from the ARM Architecture by Richard Grisenthwaite

http://www.eit.lth.se/fileadmin/eit/courses/eitf20/ARM_RG.pdf [backup]

ARMv8 Technology Preview

Talk :
http://armdevices.net/2011/11/05/armv8-technology-preview-a-highly-technical-presentation-video/
Slide:
http://www.arm.com/files/downloads/ARMv8_Architecture.pdf
ARMv8 reference manual
http://www.element14.com/community/servlet/JiveServlet/previewBody/41836-102-1-229511/ARM.Reference_Manual.pdf

Article: CPUs Have Been Doing GPU Computing Badly for Years
http://blogs.arm.com/multimedia/305-cpus-have-been-doing-gpu-computing-badly-for-years/

2012年10月10日星期三

Cross compile LnQ: Building LnQ to ARM executatble in x86 platform

Pre-requests:

llvm-gcc-arm:

../configure --prefix=/home/tk/research/llvm-qemu/tool/llvm-gcc-4.2-2.9-arm --program-prefix=llvm- --enable-llvm=/home/tk/research/llvm-qemu/llvm/install/llvm-2.9-official --target=arm-none-linux-gnueabi --with-sysroot=/home/tk/research/llvm-qemu/tool/arm-2012.03/arm-none-linux-gnueabi/libc --enable-languages=c,c++
Make sure that /home/tk/research/llvm-qemu/tool/arm-2012.03/bin in PATH
DO USE official LLVM 2.9, NOT LnQ's LLVM 2.9.

llvm-2.9 x86 version, LnQ's version

host and target set to i686-pc-linux-gnu

llvm-2.9 ARM version, LnQ's version

host and target set to arm-none-linux-gnueabi

ARM toolchain

download from

Environment setting:

LLVM_ARM=llvm-2.9-arm/bin
LLVM=llvm-2.9/bin
LLVM_GCC=llvm-gcc-4.2-2.9-arm/bin
在 PATH 設定成 LLVM_ARM 先，LLVM，再 LLVM_GCC，

LLVM_ARM 中的 llvm-link 跟 opt 要先設成非執行檔。
理由：我們需要用 $LLVM_ARM/llvm-config 來設定 LD_FLAGS，但我們也需要 $LLVM/llvm-link 跟 $LLVM/opt 這兩個檔。所以這兩個都要在 PATH 上。

LnQ configure:

加入 --cross-prefix='arm-linux-gnueabi-' --cpu=armv7l
configure --target-list=i386-linux-user --prefix=$INSTALL --enable-lnq --disable-strip --cross-prefix='arm-linux-gnueabi-' --cpu=armv7l

waste time to chase a ghost...

Question: number of workers can slow down Xalancbmk????

train input, merge used

#1: 334.756721
#2: 342.477593
#3: 376.607939
#1: 348.298319
#1: 333.039942
#3: 357.604264
#1: 331.753310
#3: 359.777587

Generate code duration? NO!

performance different, trace, i386

-3.37, perlbench
-1.25, bzip2
4.82, gcc
-1.64, mcf
0.00, gobmk
-2.72,
-2.54
-6.59
-6.90
-4.65
2.50
3.63

performance difference, region, i386

-6.61, sjeng
-6.40, h264ref
-5.31, omnetpp
-2.83, libquantum
-2.30, bzip2
-2.11, mcf
-1.65, perlbench
-1.49, gobmk
-1.11, hmmer
7.11, gcc
9.26, astar
2.00, xalancbmk

performance differece, trace, ARM

483.xalancbmk -12.53
471.omnetpp -9.11
456.hmmer -3.41
429.mcf -2.43
473.astar -2.02
403.gcc -1.33
445.gobmk -1.21
400.perlbench -1.04
464.h264ref 0.00
401.bzip2 2.22
458.sjeng 2.84
462.libquantum 7.46

performance differece, region, ARM

471.omnetpp -16.53
445.gobmk -15.13
483.xalancbmk -12.62
458.sjeng -10.03
462.libquantum -2.49
473.astar -1.83
456.hmmer -1.70
401.bzip2 -0.47
403.gcc -0.16
429.mcf 0.00
400.perlbench 0.58

2012年10月5日星期五

Latex Symbols

Relation Symbols
Symbol	Script	Symbol	Script	Symbol	Script	Symbol	Script	Symbol	Script
$\leq\,$	`\leq`	$\geq\,$	`\geq`	$\equiv\,$	`\equiv`	$\models\,$	`\models`	$\prec\,$	`\prec`
$\succ\,$	`\succ`	$\sim\,$	`\sim`	$\perp\,$	`\perp`	$\preceq\,$	`\preceq`	$\succeq\,$	`\succeq`
$\simeq\,$	`\simeq`	$\mid\,$	`\mid`	$\ll\,$	`\ll`	$\gg\,$	`\gg`	$\asymp\,$	`\asymp`
$\parallel\,$	`\parallel`	$\subset\,$	`\subset`	$\supset\,$	`\supset`	$\approx\,$	`\approx`	$\bowtie\,$	`\bowtie`
$\subseteq\,$	`\subseteq`	$\supseteq\,$	`\supseteq`	$\cong\,$	`\cong`	$\sqsubset\,$	`\sqsubset`	$\sqsupset\,$	`\sqsupset`
$\neq\,$	`\neq`	$\smile\,$	`\smile`	$\sqsubseteq\,$	`\sqsubseteq`	$\sqsupseteq\,$	`\sqsupseteq`	$\doteq\,$	`\doteq`
$\frown\,$	`\frown`	$\in\,$	`\in`	$\ni\,$	`\ni`	$\notin\,$	`\notin`	$\propto\,$	`\propto`
$\vdash\,$	`\vdash`	$\dashv\,$	`\dashv`	$<\,$	`<`	$>\,$	`>`	$=\,$	`=`

Binary Operations
Symbol	Script	Symbol	Script	Symbol	Script	Symbol	Script
$\pm\,$	`\pm`	$\cap\,$	`\cap`	$\diamond\,$	`\diamond`	$\oplus\,$	`\oplus`
$\mp\,$	`\mp`	$\cup\,$	`\cup`	$\bigtriangleup\,$	`\bigtriangleup`	$\ominus\,$	`\ominus`
$\times\,$	`\times`	$\uplus\,$	`\uplus`	$\bigtriangledown\,$	`\bigtriangledown`	$\otimes\,$	`\otimes`
$\div\,$	`\div`	$\sqcap\,$	`\sqcap`	$\triangleleft\,$	`\triangleleft`	$\oslash\,$	`\oslash`
$\ast\,$	`\ast`	$\sqcup\,$	`\sqcup`	$\triangleright\,$	`\triangleright`	$\odot\,$	`\odot`
$\star\,$	`\star`	$\vee\,$	`\vee`	$\bigcirc\,$	`\bigcirc`	$\circ\,$	`\circ`
$\dagger\,$	`\dagger`	$\wedge\,$	`\wedge`	$\bullet\,$	`\bullet`	$\setminus\,$	`\setminus`
$\ddagger\,$	`\ddagger`	$\cdot\,$	`\cdot`	$\wr\,$	`\wr`	$\amalg\,$	`\amalg`

Set and/or Logic Notation
Symbol	Script	Symbol	Script
$\exists\,$	`\exists`	$\rightarrow\,$	`\rightarrow` or `\to`
$\nexists\,$	`\nexists`	$\leftarrow\,$	`\leftarrow` or `\gets`
$\forall\,$	`\forall`	$\mapsto\,$	`\mapsto`
$\neg\,$	`\neg`	$\implies\,$	`\implies`
$\subset\,$	`\subset`	$\Rightarrow\,$	`\Rightarrow` (preferred for implication)
$\supset\,$	`\supset`	$\leftrightarrow\,$	`\leftrightarrow`
$\in\,$	`\in`	$\iff\,$	`\iff`
$\notin\,$	`\notin`	$\Leftrightarrow\,$	`\Leftrightarrow` (preferred for equivalence (iff))
$\ni\,$	`\ni`	$\top\,$	`\top`
$\land\,$	`\land`	$\bot\,$	`\bot`
$\lor\,$	`\lor`	$\emptyset\,$ and $\varnothing\,$	`\emptyset` and `\varnothing`

Delimiters
Symbol	Script	Symbol	Script	Symbol	Script	Symbol	Script
$\|\,$	`\|`	$\\|\,$	`\\|`	$/\,$	`/`	$\backslash\,$	`\backslash`
$\{\,$	`\{`	$\}\,$	`\}`	$\langle\,$	`\langle`	$\rangle\,$	`\rangle`
$\uparrow\,$	`\uparrow`	$\Uparrow\,$	`\Uparrow`	$\lceil\,$	`\lceil`	$\rceil\,$	`\rceil`
$\downarrow\,$	`\downarrow`	$\Downarrow\,$	`\Downarrow`	$\lfloor\,$	`\lfloor`	$\rfloor\,$	`\rfloor`

Greek Letters
Symbol	Script	Symbol	Script
$\Alpha\,$ and $\alpha\,$	`\Alpha` and `\alpha`	$\Nu\,$ and $\nu\,$	`\Nu` and `\nu`
$\Beta\,$ and $\beta\,$	`\Beta` and `\beta`	$\Xi\,$ and $\xi\,$	`\Xi` and `\xi`
$\Gamma\,$ and $\gamma\,$	`\Gamma` and `\gamma`	$\Omicron\,$ and $\omicron\,$	`\Omicron` and `\omicron`
$\Delta\,$ and $\delta\,$	`\Delta` and `\delta`	$\Pi\,$ , $\pi\,$ and $\varpi$	`\Pi`, `\pi` and `\varpi`
$\Epsilon\,$ , $\epsilon\,$ and $\varepsilon\,$	`\Epsilon`, `\epsilon` and `\varepsilon`	$\Rho\,$ , $\rho\,$ and $\varrho\,$	`\Rho`, `\rho` and `\varrho`
$\Zeta\,$ and $\zeta\,$	`\Zeta` and `\zeta`	$\Sigma\,$ , $\sigma\,$ and $\varsigma\,$	`\Sigma`, `\sigma` and `\varsigma`
$\Eta\,$ and $\eta\,$	`\Eta` and `\eta`	$\Tau\,$ and $\tau\,$	`\Tau` and `\tau`
$\Theta\,$ , $\theta\,$ and $\vartheta\,$	`\Theta`, `\theta` and `\vartheta`	$\Upsilon\,$ and $\upsilon\,$	`\Upsilon` and `\upsilon`
$\Iota\,$ and $\iota\,$	`\Iota` and `\iota`	$\Phi\,$ , $\phi\,$ , and $\varphi\,$	`\Phi`, `\phi` and `\varphi`
$\Kappa\,$ , $\kappa\,$ and $\varkappa\,$	`\Kappa`, `\kappa` and `\varkappa`	$\Chi\,$ and $\chi\,$	`\Chi` and `\chi`
$\Lambda\,$ and $\lambda\,$	`\Lambda` and `\lambda`	$\Psi\,$ and $\psi\,$	`\Psi` and `\psi`
$\Mu\,$ and $\mu\,$	`\Mu` and `\mu`	$\Omega\,$ and $\omega\,$	`\Omega` and `\omega`

Other symbols
Symbol	Script	Symbol	Script	Symbol	Script	Symbol	Script	Symbol	Script
$\partial\,$	`\partial`	$\imath\,$	`\imath`	$\Re\,$	`\Re`	$\nabla\,$	`\nabla`	$\aleph\,$	`\aleph`
$\eth\,$	`\eth`	$\jmath\,$	`\jmath`	$\Im\,$	`\Im`	$\Box\,$	`\Box`	$\beth\,$	`\beth`
$\hbar\,$	`\hbar`	$\ell\,$	`\ell`	$\wp\,$	`\wp`	$\infty\,$	`\infty`	$\gimel\,$	`\gimel`

Trigonometric Functions
Symbol	Script	Symbol	Script	Symbol	Script	Symbol	Script
$\sin\,$	`\sin`	$\arcsin\,$	`\arcsin`	$\sinh\,$	`\sinh`	$\sec\,$	`\sec`
$\cos\,$	`\cos`	$\arccos\,$	`\arccos`	$\cosh\,$	`\cosh`	$\csc\,$	`\csc`
$\tan\,$	`\tan`	$\arctan\,$	`\arctan`	$\tanh\,$	`\tanh`
$\cot\,$	`\cot`	$\arccot\,$	`\arccot`	$\coth\,$	`\coth`