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That's all we know. X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "open list:RISC-V" , Sagar Karandikar , Bastian Koppelmann , "qemu-devel@nongnu.org Developers" , Palmer Dabbelt , Alistair Francis , LIU Zhiwei Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --0000000000004205ab05ac042fb4 Content-Type: text/plain; charset="UTF-8" On Fri, Jul 31, 2020 at 5:24 AM Richard Henderson < richard.henderson@linaro.org> wrote: > On 7/22/20 2:16 AM, frank.chang@sifive.com wrote: > > From: Frank Chang > > > > Sign-extend vsaddu.vi immediate value. > > > > Signed-off-by: Frank Chang > > --- > > target/riscv/insn_trans/trans_rvv.inc.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/target/riscv/insn_trans/trans_rvv.inc.c > b/target/riscv/insn_trans/trans_rvv.inc.c > > index 956ee90745..3018489536 100644 > > --- a/target/riscv/insn_trans/trans_rvv.inc.c > > +++ b/target/riscv/insn_trans/trans_rvv.inc.c > > @@ -2374,7 +2374,7 @@ GEN_OPIVX_TRANS(vsaddu_vx, opivx_check) > > GEN_OPIVX_TRANS(vsadd_vx, opivx_check) > > GEN_OPIVX_TRANS(vssubu_vx, opivx_check) > > GEN_OPIVX_TRANS(vssub_vx, opivx_check) > > -GEN_OPIVI_TRANS(vsaddu_vi, IMM_ZX, vsaddu_vx, opivx_check) > > +GEN_OPIVI_TRANS(vsaddu_vi, IMM_SX, vsaddu_vx, opivx_check) > > GEN_OPIVI_TRANS(vsadd_vi, IMM_SX, vsadd_vx, opivx_check) > > > > /* Vector Single-Width Averaging Add and Subtract */ > > > > This isn't what spike does. > > The manual could really stand to be more specific here... > > > r~ > Isn't Spike's vsaddu.vi immediate value also signed-extended? *riscv/insns/vsaddu_vi.h:* *vd = vs2 + (insn.v_simm5() & (UINT64_MAX >> (64 - P.VU.vsew))); * >From RVV 0.9 spec.: *vsaddu.vi vd, vs2, imm, vm # vector-immediate* It also mentions *imm* is sign-extended. In contrast, *uimm* represents the immediate value to be zero-extended. Frank Chang --0000000000004205ab05ac042fb4 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
On Fri, Jul 31, 2020 at 5:24 AM Richard H= enderson <richard.hender= son@linaro.org> wrote:
On 7/22/20 2:16 AM, frank.chang@sifive.com wr= ote:
> From: Frank Chang <frank.chang@sifive.com>
>
> Sign-extend vsaddu.vi immediate value.
>
> Signed-off-by: Frank Chang <frank.chang@sifive.com>
> ---
>=C2=A0 target/riscv/insn_trans/trans_rvv.inc.c | 2 +-
>=C2=A0 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/target/riscv/insn_trans/trans_rvv.inc.c b/target/riscv/in= sn_trans/trans_rvv.inc.c
> index 956ee90745..3018489536 100644
> --- a/target/riscv/insn_trans/trans_rvv.inc.c
> +++ b/target/riscv/insn_trans/trans_rvv.inc.c
> @@ -2374,7 +2374,7 @@ GEN_OPIVX_TRANS(vsaddu_vx,=C2=A0 opivx_check) >=C2=A0 GEN_OPIVX_TRANS(vsadd_vx,=C2=A0 opivx_check)
>=C2=A0 GEN_OPIVX_TRANS(vssubu_vx,=C2=A0 opivx_check)
>=C2=A0 GEN_OPIVX_TRANS(vssub_vx,=C2=A0 opivx_check)
> -GEN_OPIVI_TRANS(vsaddu_vi, IMM_ZX, vsaddu_vx, opivx_check)
> +GEN_OPIVI_TRANS(vsaddu_vi, IMM_SX, vsaddu_vx, opivx_check)
>=C2=A0 GEN_OPIVI_TRANS(vsadd_vi, IMM_SX, vsadd_vx, opivx_check)
>=C2=A0
>=C2=A0 /* Vector Single-Width Averaging Add and Subtract */
>

This isn't what spike does.

The manual could really stand to be more specific here...


r~

Isn't Spike's vsaddu.vi immediate value also signed-extended?=C2=A0
riscv/insns/vsaddu_vi.h:
vd =3D vs2 + (insn= .v_simm5() & (UINT64_MAX >> (64 - P.VU.vsew)));=C2=A0

From RVV 0.9 spec.:
vsaddu.vi vd, vs2, imm, vm # vector-immediate
It als= o mentions=C2=A0imm is sign-extended.
In contrast, uimm= represents the immediate value to be zero-extended.

Frank Chang
--0000000000004205ab05ac042fb4--