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Compiler intrinsics
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ARM assembler instruction intrinsics supported by
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Compiler intrinsics for controlling IRQ and FIQ in
Compiler intrinsics for inserting optimization bar
Compiler intrinsics for inserting native instructi
Compiler intrinsics for Digital Signal Processing
European Telecommunications Standards Institute (E
Compiler support for European Telecommunications S
Overflow and carry status flags for C and C++ code
Texas Instruments (TI) C55x intrinsics for optimiz
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Compiler type attribute, __attribute__((bitband))
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Selectively applying PreCompiled Header (PCH) file
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Performance issues with PreCompiled Header (PCH) f
Default compiler options that are affected by opti
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Using the Inline and Embedded Assemblers of the AR
Compiler User Guide
Compiler intrinsics for inserting optimization barriers
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The compiler can perform a range of optimizations, including re-ordering instructions and merging some operations. In some cases, such as system level programming where memory is being accessed concurrently by multiple processes, it might be necessary to disable instruction re-ordering and force memory to be updated.
The optimization barrier intrinsics __schedule_barrier, __force_stores and __memory_changed do
not generate code, but they can result in slightly increased code
size and additional memory accesses.
Note
On some systems the memory barrier intrinsics might not be
sufficient to ensure memory consistency. For example, the __memory_changed intrinsic
forces values held in registers to be written out to memory. However,
if the destination for the data is held in a region that can be buffered
it might wait in a write buffer. In this case you might also have
to write to CP15 or use a memory barrier instruction to drain the
write buffer. See the Technical Reference Manual for your ARM processor
for more information.
See also- Reference
Compiler Reference:
- Other information
The Technical Reference Manual for your ARM processor.
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