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Compiler-specific Features
Errors
The compiler does not recognize the __ldrexd intrinsic when compiling for a target that
does not support the LDREXD instruction. The compiler generates either a warning or an
error in this case.
The __ldrexd intrinsic only supports access to doubleword data. The compiler generates
an error if you specify an access width that is not supported.
See also
• __ldrex on page 4-84
• __strex on page 4-101
• __strexd on page 4-102
• LDREX and STREX on page 4-36 in the Assembler Guide.
4.7.16 __ldrt
This intrinsic inserts an assembly language instruction of the form LDR{size}T into the
instruction stream generated by the compiler. It enables you to load data from memory
in your C or C++ code using an LDRT instruction.
Syntax
unsigned int __ldrt(const volatile void *ptr)
Where:
ptr
Points to the address of the data to be loaded frommemory. To specify the
size of the data to be loaded, cast the parameter to an appropriate integral
type.
Table 4-10 Access widths supported by the __ldrt intrinsic
Instruction a
Size of data loaded
C cast
LDRSBT signed byte (signed char *)
LDRBT unsigned byte (char *)
LDRSHT signed halfword (signed short int *)
LDRHT unsigned halfword (short int *)
LDRT word (int *)
a. Or equivalent.
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