[skip ci] Document how to quickly check if jit .dasc files transpile, how to test the jit in different architectures. #7768
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ext/opcache/jit/README.md
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| read-only, which is sometimes the cause of opcache bugs. | ||
| - `--repeat 2` is optional, but used in CI since some JIT bugs only show up after processing a | ||
| request multiple times, e.g. due to a bug in the engine or bad data in the | ||
| runtime cache of the interpreter. |
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The actual reason is that the first request compiles the trace and the second executes it.
ext/opcache/jit/README.md
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| request multiple times, e.g. due to a bug in the engine or bad data in the | ||
| runtime cache of the interpreter. | ||
| - `-j$(nproc)` runs as many workers to run tests as there are CPUs. | ||
| - `ext/opcache/` is the folder with the tests to run, in this case opcache |
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You might want to also pass Zend/
ext/opcache/jit/README.md
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| itself. If no folders are provided, all tests are run. | ||
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| When investigating test failures such as segmentation faults, adding | ||
| `-m --show-mem` may be useful to test with [valgrind](https://valgrind.org/) to detect out of bounds memory accesses. |
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We usually use --enable-address-sanitizer builds instead.
| ``` | ||
| export LDFLAGS=-L/usr/lib/i386-linux-gnu | ||
| export CFLAGS='-m32' | ||
| export CXXFLAGS='-m32' |
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It's copied from azure/i386/job.yml - it'll prevent issues if anyone adapts these instructions to --enable-intl. ./ext/intl/breakiterator/breakiterator_class.cpp
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I believe our CFLAGS also applies to C++ code, but I can't be bothered to double check...
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ext/intl/intl_convertcpp.lo: /path/to/php-src/ext/intl/intl_convertcpp.cpp
$(LIBTOOL) --mode=compile $(CXX) -Iext/intl/ -I/path/to/php-src/ext/intl/ $(COMMON_FLAGS) $(CXXFLAGS_CLEAN) $(EXTRA_CXXFLAGS) -DU_NO_DEFAULT_INCLUDE_UTF_HEADERS=1 -DU_HIDE_OBSOLETE_UTF_OLD_H=1 -Wno-write-strings -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -std=c++11 -DUNISTR_FROM_CHAR_EXPLICIT=explicit -DUNISTR_FROM_STRING_EXPLICIT=explicit -c /path/to/php-src/ext/intl/intl_convertcpp.cpp -o ext/intl/intl_convertcpp.lo -MMD -MF ext/intl/intl_convertcpp.dep -MT ext/intl/intl_convertcpp.lo
main/strlcpy.lo: /path/to/php-src/main/strlcpy.c
$(LIBTOOL) --mode=compile $(CC) -Imain/ -I/path/to/php-src/main/ $(COMMON_FLAGS) $(CFLAGS_CLEAN) $(EXTRA_CFLAGS) -DZEND_ENABLE_STATIC_TSRMLS_CACHE=1 -c /path/to/php-src/main/strlcpy.c -o main/strlcpy.lo -MMD -MF main/strlcpy.dep -MT main/strlcpy.loIf I add CFLAGS=-Wunused and then run ./config.nice, the only place -Wunused gets added is CFLAGS_CLEAN.
CFLAGS = $(CFLAGS_CLEAN) -prefer-non-pic -static
CFLAGS_CLEAN = -fno-common -Wformat-truncation -Wlogical-op -Wduplicated-cond -Wno-clobbered -Wall -Wextra -Wno-strict-aliasing -Wno-unused-parameter -Wno-sign-compare -Wunused -fvisibility=hidden -O0 -Wimplicit-fallthrough=1 -g -DZEND_SIGNALS $(PROF_FLAGS)
CPP = cc -E
CPPFLAGS = -D_GNU_SOURCE
CXX = g++
CXXFLAGS = -g -O0 -prefer-non-pic -static $(PROF_FLAGS)
CXXFLAGS_CLEAN = -g -O0
ext/opcache/jit/README.md
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| [AddressSanitizer](https://github.com/google/sanitizers/wiki/AddressSanitizer) is often useful. | ||
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| Some of the time, adding `-m --show-mem` to the `TESTS` configuration is also useful to test with [valgrind](https://valgrind.org/) to detect out of bounds memory accesses. | ||
| This is less effective at detecting or explaining invalid memory accesses than AddressSanitizer, but does not require rebuilding php. |
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Not really less effective, just much slower. You can rebuild PHP in the time it takes to run a handful of tests under valgrind ;)
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https://github.com/google/sanitizers/wiki/AddressSanitizerAlgorithm#short-version
I mean that I thought AddressSanitizer would detect the computation of an invalid address, which might be distanced from the use (read/write) of the invalid address that caused misbehaviors.
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No, address sanitizer does not detect invalid address calculations. Though I believe ubsan does, at least to a limited degree.
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Oh. Missed the * when reading that.
| ``` | ||
| export LDFLAGS=-L/usr/lib/i386-linux-gnu | ||
| export CFLAGS='-m32' | ||
| export CXXFLAGS='-m32' |
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I believe our CFLAGS also applies to C++ code, but I can't be bothered to double check...
Figured this out from the makefile - this may be useful for new contributors (of features that require modifying the jit)
Aside: I'd also figured out how to use qemu to emulate arm64 in a VM, though there are multiple steps, and the emulated VM would make building or running tests significantly slower.
(https://www.docker.com/blog/faster-multi-platform-builds-dockerfile-cross-compilation-guide/ seems easier)