Roger Chang has submitted this change. ( https://gem5-review.googlesource.com/c/public/gem5/+/70358?usp=email ) Change subject: arch-riscv: Refactor RVC decode flow when funct4==0b1001 and op==C2 ...................................................................... arch-riscv: Refactor RVC decode flow when funct4==0b1001 and op==C2 the compressed instruction 0x901e (c.add zero, t2) should be decoded as "c_add zero, t2" not c_ebreak Change-Id: Ib2bd4b4d9739aa27ad290ead313e95b11b1727d1 Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/70358 Reviewed-by: Jason Lowe-Power <power.jg@gmail.com> Maintainer: Jason Lowe-Power <power.jg@gmail.com> Tested-by: kokoro <noreply+kokoro@google.com> --- M src/arch/riscv/isa/decoder.isa 1 file changed, 11 insertions(+), 17 deletions(-) Approvals: Jason Lowe-Power: Looks good to me, approved; Looks good to me, approved kokoro: Regressions pass diff --git a/src/arch/riscv/isa/decoder.isa b/src/arch/riscv/isa/decoder.isa index d89a0c9..f22efb0 100644 --- a/src/arch/riscv/isa/decoder.isa +++ b/src/arch/riscv/isa/decoder.isa @@ -365,27 +365,21 @@ Rc1 = rvSext(Rc2); }}); } - 0x1: decode RC1 { - 0x0: SystemOp::c_ebreak({{ - if (RC2 != 0) { - return std::make_shared<IllegalInstFault>( - "source reg x1", machInst); - } - return std::make_shared<BreakpointFault>(xc->pcState()); - }}, IsSerializeAfter, IsNonSpeculative, No_OpClass); - default: decode RC2 { - 0x0: Jump::c_jalr({{ - if (RC1 == 0) { - return std::make_shared<IllegalInstFault>( - "source reg x0", machInst); - } + 0x1: decode RC2 { + 0x0: decode RC1 { + 0x0: SystemOp::c_ebreak({{ + return std::make_shared<BreakpointFault>( + xc->pcState()); + }}, IsSerializeAfter, IsNonSpeculative, No_OpClass); + default: Jump::c_jalr({{ ra = rvSext(NPC); NPC = rvZext(Rc1); }}, IsIndirectControl, IsUncondControl, IsCall); - default: CompressedROp::c_add({{ - Rc1_sd = rvSext(Rc1_sd + Rc2_sd); - }}); } + default: CompressedROp::c_add({{ + // RC1 == 0 is HINT + Rc1_sd = rvSext(Rc1_sd + Rc2_sd); + }}); } } format CompressedStore { -- To view, visit https://gem5-review.googlesource.com/c/public/gem5/+/70358?usp=email To unsubscribe, or for help writing mail filters, visit https://gem5-review.googlesource.com/settings?usp=email Gerrit-MessageType: merged Gerrit-Project: public/gem5 Gerrit-Branch: develop Gerrit-Change-Id: Ib2bd4b4d9739aa27ad290ead313e95b11b1727d1 Gerrit-Change-Number: 70358 Gerrit-PatchSet: 7 Gerrit-Owner: Roger Chang <rogerycchang@google.com> Gerrit-Reviewer: Bobby Bruce <bbruce@ucdavis.edu> Gerrit-Reviewer: Hoa Nguyen <hoanguyen@ucdavis.edu> Gerrit-Reviewer: Jason Lowe-Power <jason@lowepower.com> Gerrit-Reviewer: Jason Lowe-Power <power.jg@gmail.com> Gerrit-Reviewer: Roger Chang <rogerycchang@google.com> Gerrit-Reviewer: kokoro <noreply+kokoro@google.com> Gerrit-CC: Yu-hsin Wang <yuhsingw@google.com>