Debugger_DisassembleThumb (changes)
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Debugger
» SWI Calls
» Debugger_DisassembleThumb
Debugger_DisassembleThumb
(SWI &40381)
| Entry | |
|---|---|
| R0 | Instruction to disassemble |
| R1 | Address to disassemble relative to |
| Exit | |
|---|---|
| R1 | Pointer to null-terminated string containing disassembly |
| R2 | Length of string (excluding terminator) |
Use
The purpose of this call is to disassemble a 16bit Thumb instruction word. R1 should contain the address that the instruction came from – this allows the Debugger module to display absolute addresses for the target of PC-relative instructions (e.g. branches).
Notes
The string returned in R1 is located within the Debugger module’s workspace. Therefore care must be taken to take a copy of the string before another call to the Debugger module overwrites it.
In addition to containing the assembler mnemonic that best represents the instruction, the disassembly may also contain a comment (marked with ‘;’) that gives additional information, for example warnings about potential code bugs or potential CPU incompatibilities.
See also
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