llvm-project/compiler-rt
Roman Lebedev e8e95b5b01 [compiler-rt][X86][AMD][Bulldozer] Fix Bulldozer Model 2 detection.
Summary:
The compiler-rt side of D46314

I have discovered an issue by accident.
```
$ lscpu
Architecture:        x86_64
CPU op-mode(s):      32-bit, 64-bit
Byte Order:          Little Endian
CPU(s):              8
On-line CPU(s) list: 0-7
Thread(s) per core:  2
Core(s) per socket:  4
Socket(s):           1
NUMA node(s):        1
Vendor ID:           AuthenticAMD
CPU family:          21
Model:               2
Model name:          AMD FX(tm)-8350 Eight-Core Processor
Stepping:            0
CPU MHz:             3584.018
CPU max MHz:         4000.0000
CPU min MHz:         1400.0000
BogoMIPS:            8027.22
Virtualization:      AMD-V
L1d cache:           16K
L1i cache:           64K
L2 cache:            2048K
L3 cache:            8192K
NUMA node0 CPU(s):   0-7
Flags:               fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc cpuid extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt lwp fma4 tce nodeid_msr tbm topoext perfctr_core perfctr_nb cpb hw_pstate vmmcall bmi1 arat npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold
```
So this is model-2 bulldozer AMD CPU.

GCC agrees:
```
$ echo | gcc -E - -march=native -###
<...>
 /usr/lib/gcc/x86_64-linux-gnu/7/cc1 -E -quiet -imultiarch x86_64-linux-gnu - "-march=bdver2" -mmmx -mno-3dnow -msse -msse2 -msse3 -mssse3 -msse4a -mcx16 -msahf -mno-movbe -maes -mno-sha -mpclmul -mpopcnt -mabm -mlwp -mfma -mfma4 -mxop -mbmi -mno-sgx -mno-bmi2 -mtbm -mavx -mno-avx2 -msse4.2 -msse4.1 -mlzcnt -mno-rtm -mno-hle -mno-rdrnd -mf16c -mno-fsgsbase -mno-rdseed -mprfchw -mno-adx -mfxsr -mxsave -mno-xsaveopt -mno-avx512f -mno-avx512er -mno-avx512cd -mno-avx512pf -mno-prefetchwt1 -mno-clflushopt -mno-xsavec -mno-xsaves -mno-avx512dq -mno-avx512bw -mno-avx512vl -mno-avx512ifma -mno-avx512vbmi -mno-avx5124fmaps -mno-avx5124vnniw -mno-clwb -mno-mwaitx -mno-clzero -mno-pku -mno-rdpid --param "l1-cache-size=16" --param "l1-cache-line-size=64" --param "l2-cache-size=2048" "-mtune=bdver2"
<...>
```

But clang does not: (look for `bdver1`)
```
$ echo | clang -E - -march=native -###
clang version 7.0.0- (trunk)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/local/bin
 "/usr/lib/llvm-7/bin/clang" "-cc1" "-triple" "x86_64-pc-linux-gnu" "-E" "-disable-free" "-disable-llvm-verifier" "-discard-value-names" "-main-file-name" "-" "-mrelocation-model" "static" "-mthread-model" "posix" "-mdisable-fp-elim" "-fmath-errno" "-masm-verbose" "-mconstructor-aliases" "-munwind-tables" "-fuse-init-array" "-target-cpu" "bdver1" "-target-feature" "+sse2" "-target-feature" "+cx16" "-target-feature" "+sahf" "-target-feature" "+tbm" "-target-feature" "-avx512ifma" "-target-feature" "-sha" "-target-feature" "-gfni" "-target-feature" "+fma4" "-target-feature" "-vpclmulqdq" "-target-feature" "+prfchw" "-target-feature" "-bmi2" "-target-feature" "-cldemote" "-target-feature" "-fsgsbase" "-target-feature" "-xsavec" "-target-feature" "+popcnt" "-target-feature" "+aes" "-target-feature" "-avx512bitalg" "-target-feature" "-xsaves" "-target-feature" "-avx512er" "-target-feature" "-avx512vnni" "-target-feature" "-avx512vpopcntdq" "-target-feature" "-clwb" "-target-feature" "-avx512f" "-target-feature" "-clzero" "-target-feature" "-pku" "-target-feature" "+mmx" "-target-feature" "+lwp" "-target-feature" "-rdpid" "-target-feature" "+xop" "-target-feature" "-rdseed" "-target-feature" "-waitpkg" "-target-feature" "-ibt" "-target-feature" "+sse4a" "-target-feature" "-avx512bw" "-target-feature" "-clflushopt" "-target-feature" "+xsave" "-target-feature" "-avx512vbmi2" "-target-feature" "-avx512vl" "-target-feature" "-avx512cd" "-target-feature" "+avx" "-target-feature" "-vaes" "-target-feature" "-rtm" "-target-feature" "+fma" "-target-feature" "+bmi" "-target-feature" "-rdrnd" "-target-feature" "-mwaitx" "-target-feature" "+sse4.1" "-target-feature" "+sse4.2" "-target-feature" "-avx2" "-target-feature" "-wbnoinvd" "-target-feature" "+sse" "-target-feature" "+lzcnt" "-target-feature" "+pclmul" "-target-feature" "-prefetchwt1" "-target-feature" "+f16c" "-target-feature" "+ssse3" "-target-feature" "-sgx" "-target-feature" "-shstk" "-target-feature" "+cmov" "-target-feature" "-avx512vbmi" "-target-feature" "-movbe" "-target-feature" "-xsaveopt" "-target-feature" "-avx512dq" "-target-feature" "-adx" "-target-feature" "-avx512pf" "-target-feature" "+sse3" "-dwarf-column-info" "-debugger-tuning=gdb" "-resource-dir" "/usr/lib/llvm-7/lib/clang/7.0.0" "-internal-isystem" "/usr/local/include" "-internal-isystem" "/usr/lib/llvm-7/lib/clang/7.0.0/include" "-internal-externc-isystem" "/usr/include/x86_64-linux-gnu" "-internal-externc-isystem" "/include" "-internal-externc-isystem" "/usr/include" "-fdebug-compilation-dir" "/build/llvm-build-Clang-release" "-ferror-limit" "19" "-fmessage-length" "271" "-fobjc-runtime=gcc" "-fdiagnostics-show-option" "-fcolor-diagnostics" "-o" "-" "-x" "c" "-"
```

So clang, unlike gcc, considers this to be `bdver1`.

After some digging, i've come across `getAMDProcessorTypeAndSubtype()` in `Host.cpp`.
I have added the following debug printf after the call to that function in `sys::getHostCPUName()`:
```
errs() << "Family " << Family << " Model " << Model << " Type " << Type "\n";
```
Which produced:
```
Family 21 Model 2 Type 5
```
Which matches the `lscpu` output.

As it was pointed in the review by @craig.topper:
>>! In D46314#1084123, @craig.topper wrote:
> I dont' think this is right. Here is what I found on wikipedia. https://en.wikipedia.org/wiki/List_of_AMD_CPU_microarchitectures.
>
> AMD Bulldozer Family 15h - the successor of 10h/K10. Bulldozer is designed for processors in the 10 to 220W category, implementing XOP, FMA4 and CVT16 instruction sets. Orochi was the first design which implemented it. For Bulldozer, CPUID model numbers are 00h and 01h.
> AMD Piledriver Family 15h (2nd-gen) - successor to Bulldozer. CPUID model numbers are 02h (earliest "Vishera" Piledrivers) and 10h-1Fh.
> AMD Steamroller Family 15h (3rd-gen) - third-generation Bulldozer derived core. CPUID model numbers are 30h-3Fh.
> AMD Excavator Family 15h (4th-gen) - fourth-generation Bulldozer derived core. CPUID model numbers are 60h-6Fh, later updated revisions have model numbers 70h-7Fh.
>
>
> So there's a weird exception where model 2 should go with 0x10-0x1f.

Though It does not help that the code can't be tested at the moment.
With this logical change, the `bdver2` is properly detected.
```
$ echo | /build/llvm-build-Clang-release/bin/clang -E - -march=native -###
clang version 7.0.0 (trunk 331249) (llvm/trunk 331256)
Target: x86_64-unknown-linux-gnu
Thread model: posix
InstalledDir: /build/llvm-build-Clang-release/bin
 "/build/llvm-build-Clang-release/bin/clang-7" "-cc1" "-triple" "x86_64-unknown-linux-gnu" "-E" "-disable-free" "-main-file-name" "-" "-mrelocation-model" "static" "-mthread-model" "posix" "-mdisable-fp-elim" "-fmath-errno" "-masm-verbose" "-mconstructor-aliases" "-munwind-tables" "-fuse-init-array" "-target-cpu" "bdver2" "-target-feature" "+sse2" "-target-feature" "+cx16" "-target-feature" "+sahf" "-target-feature" "+tbm" "-target-feature" "-avx512ifma" "-target-feature" "-sha" "-target-feature" "-gfni" "-target-feature" "+fma4" "-target-feature" "-vpclmulqdq" "-target-feature" "+prfchw" "-target-feature" "-bmi2" "-target-feature" "-cldemote" "-target-feature" "-fsgsbase" "-target-feature" "-xsavec" "-target-feature" "+popcnt" "-target-feature" "+aes" "-target-feature" "-avx512bitalg" "-target-feature" "-movdiri" "-target-feature" "-xsaves" "-target-feature" "-avx512er" "-target-feature" "-avx512vnni" "-target-feature" "-avx512vpopcntdq" "-target-feature" "-clwb" "-target-feature" "-avx512f" "-target-feature" "-clzero" "-target-feature" "-pku" "-target-feature" "+mmx" "-target-feature" "+lwp" "-target-feature" "-rdpid" "-target-feature" "+xop" "-target-feature" "-rdseed" "-target-feature" "-waitpkg" "-target-feature" "-movdir64b" "-target-feature" "-ibt" "-target-feature" "+sse4a" "-target-feature" "-avx512bw" "-target-feature" "-clflushopt" "-target-feature" "+xsave" "-target-feature" "-avx512vbmi2" "-target-feature" "-avx512vl" "-target-feature" "-avx512cd" "-target-feature" "+avx" "-target-feature" "-vaes" "-target-feature" "-rtm" "-target-feature" "+fma" "-target-feature" "+bmi" "-target-feature" "-rdrnd" "-target-feature" "-mwaitx" "-target-feature" "+sse4.1" "-target-feature" "+sse4.2" "-target-feature" "-avx2" "-target-feature" "-wbnoinvd" "-target-feature" "+sse" "-target-feature" "+lzcnt" "-target-feature" "+pclmul" "-target-feature" "-prefetchwt1" "-target-feature" "+f16c" "-target-feature" "+ssse3" "-target-feature" "-sgx" "-target-feature" "-shstk" "-target-feature" "+cmov" "-target-feature" "-avx512vbmi" "-target-feature" "-movbe" "-target-feature" "-xsaveopt" "-target-feature" "-avx512dq" "-target-feature" "-adx" "-target-feature" "-avx512pf" "-target-feature" "+sse3" "-dwarf-column-info" "-debugger-tuning=gdb" "-resource-dir" "/build/llvm-build-Clang-release/lib/clang/7.0.0" "-internal-isystem" "/usr/local/include" "-internal-isystem" "/build/llvm-build-Clang-release/lib/clang/7.0.0/include" "-internal-externc-isystem" "/usr/include/x86_64-linux-gnu" "-internal-externc-isystem" "/include" "-internal-externc-isystem" "/usr/include" "-fdebug-compilation-dir" "/build/llvm-build-Clang-release" "-ferror-limit" "19" "-fmessage-length" "271" "-fobjc-runtime=gcc" "-fdiagnostics-show-option" "-fcolor-diagnostics" "-o" "-" "-x" "c" "-"
```

Reviewers: craig.topper, asbirlea, rnk, GGanesh, andreadb

Reviewed By: craig.topper

Subscribers: sdardis, dberris, aprantl, arichardson, JDevlieghere, #sanitizers, llvm-commits, cfe-commits, craig.topper

Differential Revision: https://reviews.llvm.org/D46323

llvm-svn: 331295
2018-05-01 18:40:15 +00:00
..
cmake Revert "[CMake] Make simple source used for CMake checks a C file" 2018-04-27 01:25:32 +00:00
docs [sanitizers] Make it possible to XFAIL on the effective target, not just the default. 2016-08-09 11:50:53 +00:00
include [scudo] Adding an interface function to print allocator stats 2018-04-25 18:52:29 +00:00
lib [compiler-rt][X86][AMD][Bulldozer] Fix Bulldozer Model 2 detection. 2018-05-01 18:40:15 +00:00
test tsan: improve "destroy of a locked mutex" reports 2018-04-27 08:59:35 +00:00
unittests Allow compiler-rt test targets to work with multi-config CMake generators 2017-11-13 12:57:54 +00:00
utils Remove more references to ptrace_pt_{g,s}et_sigmask 2018-03-03 18:41:38 +00:00
www
.arcconfig [compiler-rt] Set up .arcconfig to point to new Diffusion CRT repository 2017-12-06 20:55:32 +00:00
.gitignore Add .pyc files to .gitignore to compiler-rt 2017-07-24 21:51:12 +00:00
CMakeLists.txt Enable full debug info in the ASan runtime on Windows 2018-04-26 20:34:19 +00:00
CODE_OWNERS.TXT [sanitizers] remove earthdok@ from owners 2016-05-18 18:52:18 +00:00
CREDITS.TXT
LICENSE.TXT Update copyright year to 2016. 2016-03-30 22:38:50 +00:00
README.txt

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Compiler-RT
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Compiler-RT is open source software. You may freely distribute it under the
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