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__svc_indirect_r7

__value_in_regs

__declspec attributes

__declspec(dllexport)

__declspec(dllimport)

__declspec(noinline)

__declspec(noreturn)

__declspec(nothrow)

__declspec(notshared)

__declspec(thread)

Function attributes

__attribute__((alias))

__attribute__((always_inline))

__attribute__((const))

__attribute__((deprecated))

__attribute__((malloc))

__attribute__((noinline))

__attribute__((noreturn))

__attribute__((pure))

__attribute__((section))

__attribute__((unused))

__attribute__((used))

__attribute__((weak))

Type attributes

__attribute__((aligned))

__attribute((packed))

__attribute__((transparent_union))

Variable attributes

__attribute__((alias))

__attribute__((at(address)))

__attribute__((aligned))

__attribute__((deprecated))

__attribute__((packed))

__attribute__((section))

__attribute__((transparent_union))

__attribute__((unused))

__attribute__((used))

__attribute__((weak))

__attribute__((zero_init))

#pragma [no_]anon_unions

#pragma arm section [section_sort_list]

#pragma diag_default tag[,tag,...]

#pragma diag_error tag[,tag,...]

#pragma diag_remark tag[,tag,...]

#pragma diag_suppress tag[,tag,...]

#pragma diag_warning tag[, tag, ...]

#pragma [no_]exceptions_unwind

#pragma hdrstop

#pragma import symbol_name

#pragma [no_]inline

#pragma [no_]softfp_linkage

#pragma unroll [(n)]

#pragma unroll_completely

Instruction intrinsics

__builtin_constant_p

__builtin_expect

__builtin_frame_address

__builtin_return_address

__builtin_popcount

__memory_changed

__return_address

__schedule_barrier

ARMv6 SIMD intrinsics

ETSI basic operations

C55x intrinsics

Named register variables

Compiler predefines

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C and C++ Implementation Details

Via File Syntax

Standard C Implementation Definition

Standard C++ Implementation Definition

C and C++ Compiler Implementation Limits

__builtin_expect

RealView^® Compilation Tools for μVision Compiler Reference Guide

Version 3.1

Home > Compiler-specific Features > Instruction intrinsics > __builtin_expect

4.7.4. `__builtin_expect`

This intrinsic provides the compiler with branch prediction information. Calling __builtin_expect(expr, , c) informs the compiler that it is expected that expr == c.

Note

This builtin function is a GNU compiler extension that is supported by the ARM compiler.

Syntax

long __builtin_expect(long int expr, long int c)

Where:

expr: is an integral expression
c: is a compile‑time constant.

Return value

__builtin_expect returns the value of expr.

Example

if (__builtin_expect(i, 0))
{
    foo();                   // we do not expect foo to be called,
}                            // because we expect i to be zero

Copyright © 2007 ARM Limited. All rights reserved.	ARM DUI 0376A
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