9.5
General-purpose Registers
How the CC-RH uses the general-purpose registers are as follows.
Table 9.5 | Using General-purpose Registers |
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r0
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Used for operation as value of 0.
Base register of .data/.bss section reference
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r1
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caller save register
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r2
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caller save register
Reserved for system (OS) (Switched via option)
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r3 (sp)
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Stack pointer
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r4 (gp)
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Global pointer for PID
Fixed
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r5 (tp)
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Global pointer for constant data
caller save register
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r6 to r19
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caller save register
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r20 to r29
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callee save register
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r30 (ep)
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Element pointer
Fixed or callee save register (Switched via option)
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r31 (lp)
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Link pointer
callee save register
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