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https://gitlab.isc.org/isc-projects/bind9
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e603983ec9
The __builtin_expect() can be used to provide the compiler with branch
prediction information. The Gcc manual says[1] on the subject:
In general, you should prefer to use actual profile feedback for
this (-fprofile-arcs), as programmers are notoriously bad at
predicting how their programs actually perform.
Stop using __builtin_expect() and ISC_LIKELY() and ISC_UNLIKELY() macros
to provide the branch prediction information as the performance testing
shows that named performs better when the __builtin_expect() is not
being used.
1. https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#index-_005f_005fbuiltin_005fexpect
76 lines
709 B
Plaintext
76 lines
709 B
Plaintext
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statement S;
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expression V;
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- V =
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isc_buffer_allocate(...);
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- if (V != ISC_R_SUCCESS) S
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statement S1, S2;
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expression V;
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- V =
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isc_buffer_allocate(...);
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- if (V == ISC_R_SUCCESS)
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S1
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- else S2
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expression V;
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- V =
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isc_buffer_allocate(...);
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- check_result(V, ...);
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@@
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- CHECK(
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isc_buffer_allocate(...)
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- )
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;
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@@
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- DO(...,
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isc_buffer_allocate(...)
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- )
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;
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@@
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- RETERR(
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isc_buffer_allocate(...)
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- )
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;
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expression V;
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- V =
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isc_buffer_allocate(...);
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- assert_int_equal(V, ISC_R_SUCCESS);
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expression V;
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- V =
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isc_buffer_allocate(...);
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- CHECK(..., V);
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expression V;
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@@
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- V =
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isc_buffer_allocate(...);
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- RUNTIME_CHECK(V == ISC_R_SUCCESS);
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