implementation for shift left logical immediate riscv32im #2836
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## master #2836 +/- ##
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- Coverage 72.04% 72.02% -0.03%
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Files 256 257 +1
Lines 60138 60759 +621
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+ Hits 43329 43761 +432
- Misses 16809 16998 +189 ☔ View full report in Codecov by Sentry. |
| let local_rs1 = env.read_register(&rs1); | ||
| let shamt = { | ||
| let pos = env.alloc_scratch(); | ||
| unsafe { env.bitmask(&imm, 4, 0, pos) } |
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Is it not 5?
/// Format: `slli rd, rs1, shamt`
///
/// Description: Performs logical left shift on the value in register rs1 by
/// the shift amount held in the lower 5 bits of the immediate
| unsafe { env.bitmask(&imm, 4, 0, pos) } | ||
| }; | ||
| // parse shamt from imm as 20-24 of instruction and 0-4 wrt to imm | ||
| let rd_scratch = env.alloc_scratch(); |
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Nit: I would simply keep the same syntax as the others to allocate variables, like:
let local_rd = {
let pos = env.alloc_scratch();
unsafe { env.shift_left(&local_rs1, &shamt, rd_scratch) }
};But it is a very small detail.
| let local_rs1 = env.read_register(&rs1); | ||
| let shamt = { | ||
| let pos = env.alloc_scratch(); | ||
| unsafe { env.bitmask(&imm, 4, 0, pos) } |
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There must also be constraints that it is actually 5 bits, and also the 5 lowest bits of the immediate.
| unimplemented!("ShiftLeftLogicalImmediate") | ||
| // slli: x[rd] = x[rs1] << shamt | ||
| let local_rs1 = env.read_register(&rs1); | ||
| let shamt = { |
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Can you add some FIXME reg. this comment please? Can be done later.
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Note that a test is ready in master reg. sll, see assembly code. Only lui should be implemented.
| let pos = env.alloc_scratch(); | ||
| unsafe { env.bitmask(&imm, 5, 0, pos) } | ||
| }; | ||
| // parse shamt from imm as 20-24 of instruction and 0-4 wrt to imm |
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it was removed, but it was explaining where in the instruction and immediate the shamt was parsed from.
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