server-skynet-source-3rd-je.../src/jemalloc_cpp.cpp

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#include <mutex>
#include <new>
#define JEMALLOC_CPP_CPP_
#ifdef __cplusplus
extern "C" {
#endif
#include "jemalloc/internal/jemalloc_preamble.h"
#include "jemalloc/internal/jemalloc_internal_includes.h"
#ifdef __cplusplus
}
#endif
// All operators in this file are exported.
// Possibly alias hidden versions of malloc and sdallocx to avoid an extra plt
// thunk?
//
// extern __typeof (sdallocx) sdallocx_int
// __attribute ((alias ("sdallocx"),
// visibility ("hidden")));
//
// ... but it needs to work with jemalloc namespaces.
void *operator new(std::size_t size);
void *operator new[](std::size_t size);
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void *operator new(std::size_t size, const std::nothrow_t &) noexcept;
void *operator new[](std::size_t size, const std::nothrow_t &) noexcept;
void operator delete(void *ptr) noexcept;
void operator delete[](void *ptr) noexcept;
void operator delete(void *ptr, const std::nothrow_t &) noexcept;
void operator delete[](void *ptr, const std::nothrow_t &) noexcept;
#if __cpp_sized_deallocation >= 201309
/* C++14's sized-delete operators. */
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void operator delete(void *ptr, std::size_t size) noexcept;
void operator delete[](void *ptr, std::size_t size) noexcept;
#endif
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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#if __cpp_aligned_new >= 201606
/* C++17's over-aligned operators. */
void *operator new(std::size_t size, std::align_val_t);
void *operator new(std::size_t size, std::align_val_t, const std::nothrow_t &) noexcept;
void *operator new[](std::size_t size, std::align_val_t);
void *operator new[](std::size_t size, std::align_val_t, const std::nothrow_t &) noexcept;
void operator delete(void* ptr, std::align_val_t) noexcept;
void operator delete(void* ptr, std::align_val_t, const std::nothrow_t &) noexcept;
void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept;
void operator delete[](void* ptr, std::align_val_t) noexcept;
void operator delete[](void* ptr, std::align_val_t, const std::nothrow_t &) noexcept;
void operator delete[](void* ptr, std::size_t size, std::align_val_t al) noexcept;
#endif
JEMALLOC_NOINLINE
static void *
handleOOM(std::size_t size, bool nothrow) {
void *ptr = nullptr;
while (ptr == nullptr) {
std::new_handler handler;
// GCC-4.8 and clang 4.0 do not have std::get_new_handler.
{
static std::mutex mtx;
std::lock_guard<std::mutex> lock(mtx);
handler = std::set_new_handler(nullptr);
std::set_new_handler(handler);
}
if (handler == nullptr)
break;
try {
handler();
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} catch (const std::bad_alloc &) {
break;
}
ptr = je_malloc(size);
}
if (ptr == nullptr && !nothrow)
std::__throw_bad_alloc();
return ptr;
}
template <bool IsNoExcept>
JEMALLOC_ALWAYS_INLINE
void *
newImpl(std::size_t size) noexcept(IsNoExcept) {
void *ptr = je_malloc(size);
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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if (likely(ptr != nullptr)) {
return ptr;
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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}
return handleOOM(size, IsNoExcept);
}
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#if __cpp_aligned_new >= 201606
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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template <bool IsNoExcept>
JEMALLOC_ALWAYS_INLINE
void *
alignedNewImpl(std::size_t size, std::align_val_t alignment) noexcept(IsNoExcept) {
void *ptr = je_aligned_alloc(static_cast<std::size_t>(alignment), size);
if (likely(ptr != nullptr)) {
return ptr;
}
return handleOOM(size, IsNoExcept);
}
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#endif // __cpp_aligned_new
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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JEMALLOC_ALWAYS_INLINE
void
sizedDeleteImpl(void* ptr, std::size_t size) noexcept {
if (unlikely(ptr == nullptr)) {
return;
}
je_sdallocx_noflags(ptr, size);
}
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#if __cpp_aligned_new >= 201606
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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JEMALLOC_ALWAYS_INLINE
void
alignedSizedDeleteImpl(void* ptr, std::size_t size, std::align_val_t alignment) noexcept {
if (config_debug) {
assert(((size_t)alignment & ((size_t)alignment - 1)) == 0);
}
if (unlikely(ptr == nullptr)) {
return;
}
je_sdallocx(ptr, size, MALLOCX_ALIGN(alignment));
}
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#endif // __cpp_aligned_new
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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void *
operator new(std::size_t size) {
return newImpl<false>(size);
}
void *
operator new[](std::size_t size) {
return newImpl<false>(size);
}
void *
operator new(std::size_t size, const std::nothrow_t &) noexcept {
return newImpl<true>(size);
}
void *
operator new[](std::size_t size, const std::nothrow_t &) noexcept {
return newImpl<true>(size);
}
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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#if __cpp_aligned_new >= 201606
void *
operator new(std::size_t size, std::align_val_t alignment) {
return alignedNewImpl<false>(size, alignment);
}
void *
operator new(std::size_t size, std::align_val_t alignment, const std::nothrow_t &) noexcept {
return alignedNewImpl<true>(size, alignment);
}
void *
operator new[](std::size_t size, std::align_val_t alignment) {
return alignedNewImpl<false>(size, alignment);
}
void *
operator new[](std::size_t size, std::align_val_t alignment, const std::nothrow_t &) noexcept {
return alignedNewImpl<true>(size, alignment);
}
#endif // __cpp_aligned_new
void
operator delete(void *ptr) noexcept {
je_free(ptr);
}
void
operator delete[](void *ptr) noexcept {
je_free(ptr);
}
void
operator delete(void *ptr, const std::nothrow_t &) noexcept {
je_free(ptr);
}
void operator delete[](void *ptr, const std::nothrow_t &) noexcept {
je_free(ptr);
}
#if __cpp_sized_deallocation >= 201309
void
operator delete(void *ptr, std::size_t size) noexcept {
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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sizedDeleteImpl(ptr, size);
}
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
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void
operator delete[](void *ptr, std::size_t size) noexcept {
sizedDeleteImpl(ptr, size);
}
#endif // __cpp_sized_deallocation
Support C++17 over-aligned allocation Summary: Add support for C++17 over-aligned allocation: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0035r4.html Supporting all 10 operators means we avoid thunking thru libstdc++-v3/libsupc++ and just call jemalloc directly. It's also worth noting that there is now an aligned *and sized* operator delete: ``` void operator delete(void* ptr, std::size_t size, std::align_val_t al) noexcept; ``` If JeMalloc did not provide this, the default implementation would ignore the size parameter entirely: https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/libsupc%2B%2B/del_opsa.cc#L30-L33 (I must also update ax_cxx_compile_stdcxx.m4 to a newer version with C++17 support.) Test Plan: Wrote a simple test that allocates and then deletes an over-aligned type: ``` struct alignas(32) Foo {}; Foo *f; int main() { f = new Foo; delete f; } ``` Before this change, both new and delete go thru PLT, and we end up calling regular old free: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x00000000004029b7 <+55>: call 0x4022d0 <_ZnwmSt11align_val_t@plt> ... 0x00000000004029d5 <+85>: call 0x4022e0 <_ZdlPvmSt11align_val_t@plt> ... (gdb) s free (ptr=0x7ffff6408020) at /home/engshare/third-party2/jemalloc/master/src/jemalloc.git-trunk/src/jemalloc.c:2842 2842 if (!free_fastpath(ptr, 0, false)) { ``` After this change, we directly call new/delete and ultimately call sdallocx: ``` (gdb) disassemble Dump of assembler code for function main(): ... 0x0000000000402b77 <+55>: call 0x496ca0 <operator new(unsigned long, std::align_val_t)> ... 0x0000000000402b95 <+85>: call 0x496e60 <operator delete(void*, unsigned long, std::align_val_t)> ... (gdb) s 116 je_sdallocx_noflags(ptr, size); ```
2019-10-27 14:28:42 +08:00
#if __cpp_aligned_new >= 201606
void
operator delete(void* ptr, std::align_val_t) noexcept {
je_free(ptr);
}
void
operator delete(void* ptr, std::align_val_t, const std::nothrow_t&) noexcept {
je_free(ptr);
}
void
operator delete[](void* ptr, std::align_val_t) noexcept {
je_free(ptr);
}
void
operator delete[](void* ptr, std::align_val_t, const std::nothrow_t&) noexcept {
je_free(ptr);
}
void
operator delete(void* ptr, std::size_t size, std::align_val_t alignment) noexcept {
alignedSizedDeleteImpl(ptr, size, alignment);
}
void
operator delete[](void* ptr, std::size_t size, std::align_val_t alignment) noexcept {
alignedSizedDeleteImpl(ptr, size, alignment);
}
#endif // __cpp_aligned_new