[hw][dispatcher] Tag full vd..vd+nf for segment loads/stores#454
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sjalloq wants to merge 1 commit intopulp-platform:mainfrom
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[hw][dispatcher] Tag full vd..vd+nf for segment loads/stores#454sjalloq wants to merge 1 commit intopulp-platform:mainfrom
sjalloq wants to merge 1 commit intopulp-platform:mainfrom
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The per-vreg EEW tracker (eew_d[]) is updated when an instruction writes a destination vreg, but the existing loop only iterates over EMUL consecutive registers. Segment loads/stores write (NF+1)*EMUL consecutive vregs (vd, vd+1, ..., vd+nf at each EMUL group), so all but the base vd were left at the reset-default EW8. Fix: when the op is a segment load/store (VLE/VLSE/VLXE/VSE/VSSE/VSXE with nf != 0), extend the tracker update loop to cover (nf+1)*EMUL consecutive vregs. The bug was hidden in the existing rv64uv segment tests because VCLEAR (used as a defensive reset before each test) does `vmv.v.i v_reg, 0` at the test's vsew, which side-effects the EEW tracker into the matching state for v_reg. Tests that lack this pre-tagging surface the bug.
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This is the fix for #454 |
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The per-vreg EEW tracker (eew_d[]) is updated when an instruction writes a destination vreg, but the existing loop only iterates over EMUL consecutive registers. Segment loads/stores write (NF+1)*EMUL consecutive vregs (vd, vd+1, ..., vd+nf at each EMUL group), so all but the base vd were left at the reset-default EW8.
Fix: when the op is a segment load/store (VLE/VLSE/VLXE/VSE/VSSE/VSXE with nf != 0), extend the tracker update loop to cover (nf+1)*EMUL consecutive vregs.
The bug was hidden in the existing rv64uv segment tests because VCLEAR (used as a defensive reset before each test) does
vmv.v.i v_reg, 0at the test's vsew, which side-effects the EEW tracker into the matching state for v_reg. Tests that lack this pre-tagging surface the bug.Description of PR that completes issue here...
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