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riscv-non-isa / riscv-trace-spec

RISC-V Processor Trace Specification
https://jira.riscv.org/browse/RVG-88
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Should delta address field be added a sign bit at MSB? #136

Closed zhangdujiao closed 3 weeks ago

zhangdujiao commented 3 weeks ago

For 64 bits address, if the delta address is "0x0 - 0x4", how to express the result? Should a sign bit be added at MSB to show minus?

IainCRobertson commented 3 weeks ago

That's not necessary and there's nothing special about 64 bits. 0 - 4 = 0xffffffff fffffffc. If this is reported as the delta, and it is added to the base address (0) the result will be 0xffffffff fffffffc, which is the correct answer.

Iain

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For 64 bits address, if the delta address is "0x0 - 0x4", how to express the result? Should a sign bit be added at MSB to show minus?

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