Improve the division emulation in the Arm backend #136
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src/arm.c
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| return arm_transfer(cond, 0, 1, rn, rd, ofs); | ||
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| int __push(arm_cond_t cond, int reg_list) |
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Both push and pop are pseudo-instructions. Can you avoid them?
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After reading ARM Architecture Reference Manual, I understand that push and pop are equivalent to stmdb and ldmia, respectively. But I don't see any description stating that push and pop are pseudo-instructions.
May I ask where it describes push and pop as pseudo-instructions? Although I can replace them with stmdb and ldmia, I want to understand push and pop further first before improving the implementation.
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May I ask where it describes
pushandpopas pseudo-instructions?
See https://developer.arm.com/documentation/dui0489/i/arm-and-thumb-instructions/pop
Both __push and __pop are too generic, likely leading to unexpected symbol conflicts.
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Both push and pop are pseudo-instructions. Can you avoid them?
I think I misunderstood at the beginning. Originally, I thought it was related to code generation for Arm32 output.
However, the requested changes just entail that I should replace __push and __pop with __stmdb and __ldm in arm.c and arm-codegen.c. The purpose is to avoid symbol conflicts during compilation.
Is my understanding correct?
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However, the requested changes just entail that I should replace
__pushand__popwith__stmdband__ldminarm.candarm-codegen.c. The purpose is to avoid symbol conflicts during compilation.
Exactly. Unless we can change symbol visibility on demand, we must handle symbol conflicts with care.
This commit improves the division emulation in the Arm backend to enhance code reusability and eliminate potential issues. Close sysprog21#135
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Thank @DrXiao for contributing! |
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This commit improves the division emulation in the Arm backend to enhance code reusability and eliminate potential issues.
Close #135