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Overview of the Assembler Overview of the ARM Architecture Structure of Assembly Language Modules 
Writing ARM Assembly Language Unified Assembler Language Subroutines calls Load immediates into registers Load immediate values using MOV and MVN Load 32-bit values to a register using MOV32 Load immediate 32-bit values to a register using L Literal pools Load addresses into registers Load addresses to a register using ADR Load addresses to a register using ADRL Load addresses to a register using LDR Rd, =label Other ways to Load and store registers Load and store multiple register instructions Load and store multiple instructions available in Stack implementation using LDM and STM Stack operations for nested subroutines Block copy with LDM and STM Memory accesses Read-Modify-Write procedure Optional hash Use of macros Test-and-branch macro example Unsigned integer division macro example Instruction and directive relocations Symbol versions Frame directives Exception tables and Unwind tables Assembly language changes after RVCTv2.1 Condition Codes Using the Assembler Symbols, Literals, Expressions, and Operators VFP ProgrammingLoad immediate 32-bit values to a register using LDR Rd, =const
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The LDR Rd,= pseudo-instruction can construct any 32-bit numeric value in a single instruction. You can use this pseudo-instruction to generate constants that are out of range of the constMOV and MVN instructions.
The LDR pseudo-instruction generates the most efficient single instruction for the specified immediate value:
If the immediate value can be constructed with a single
MOVorMVNinstruction, the assembler generates the appropriate instruction.If the immediate value cannot be constructed with a single
MOVorMVNinstruction, the assembler:places the value in a literal pool (a portion of memory embedded in the code to hold constant values)
generates an
LDRinstruction with a PC-relative address that reads the constant from the literal pool.
For example:
LDR rn, [pc, #offset to literal pool] ; load registernwith one word ; from the address [pc + offset]You must ensure that there is a literal pool within range of the
LDRinstruction generated by the assembler.
See also- Concepts
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Assembler Reference:
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