From 3363277525958e173b4526f9dca225e125b1a5de Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Fr=C3=A9d=C3=A9ric=20P=C3=A9trot?= Date: Sun, 10 Jul 2022 13:04:51 +0200 Subject: [PATCH] target/riscv: fix shifts shamt value for rv128c MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit For rv128c shifts, a shamt of 0 is a shamt of 64, while for rv32c/rv64c it stays 0 and is a hint instruction that does not change processor state. For rv128c right shifts, the 6-bit shamt is in addition sign extended to 7 bits. Signed-off-by: Frédéric Pétrot Reviewed-by: Weiwei Li Reviewed-by: Richard Henderson Message-Id: <20220710110451.245567-1-frederic.petrot@univ-grenoble-alpes.fr> Signed-off-by: Alistair Francis --- disas/riscv.c | 27 +++++++++++++++++++++------ target/riscv/insn16.decode | 7 ++++--- target/riscv/translate.c | 20 ++++++++++++++++++-- 3 files changed, 43 insertions(+), 11 deletions(-) diff --git a/disas/riscv.c b/disas/riscv.c index 7af6afc8fa..489c2ae5e8 100644 --- a/disas/riscv.c +++ b/disas/riscv.c @@ -2402,10 +2402,25 @@ static int32_t operand_sbimm12(rv_inst inst) ((inst << 56) >> 63) << 11; } -static uint32_t operand_cimmsh6(rv_inst inst) +static uint32_t operand_cimmshl6(rv_inst inst, rv_isa isa) { - return ((inst << 51) >> 63) << 5 | + int imm = ((inst << 51) >> 63) << 5 | (inst << 57) >> 59; + if (isa == rv128) { + imm = imm ? imm : 64; + } + return imm; +} + +static uint32_t operand_cimmshr6(rv_inst inst, rv_isa isa) +{ + int imm = ((inst << 51) >> 63) << 5 | + (inst << 57) >> 59; + if (isa == rv128) { + imm = imm | (imm & 32) << 1; + imm = imm ? imm : 64; + } + return imm; } static int32_t operand_cimmi(rv_inst inst) @@ -2529,7 +2544,7 @@ static uint32_t operand_rnum(rv_inst inst) /* decode operands */ -static void decode_inst_operands(rv_decode *dec) +static void decode_inst_operands(rv_decode *dec, rv_isa isa) { rv_inst inst = dec->inst; dec->codec = opcode_data[dec->op].codec; @@ -2652,7 +2667,7 @@ static void decode_inst_operands(rv_decode *dec) case rv_codec_cb_sh6: dec->rd = dec->rs1 = operand_crs1rdq(inst) + 8; dec->rs2 = rv_ireg_zero; - dec->imm = operand_cimmsh6(inst); + dec->imm = operand_cimmshr6(inst, isa); break; case rv_codec_ci: dec->rd = dec->rs1 = operand_crs1rd(inst); @@ -2667,7 +2682,7 @@ static void decode_inst_operands(rv_decode *dec) case rv_codec_ci_sh6: dec->rd = dec->rs1 = operand_crs1rd(inst); dec->rs2 = rv_ireg_zero; - dec->imm = operand_cimmsh6(inst); + dec->imm = operand_cimmshl6(inst, isa); break; case rv_codec_ci_16sp: dec->rd = rv_ireg_sp; @@ -3193,7 +3208,7 @@ disasm_inst(char *buf, size_t buflen, rv_isa isa, uint64_t pc, rv_inst inst) dec.pc = pc; dec.inst = inst; decode_inst_opcode(&dec, isa); - decode_inst_operands(&dec); + decode_inst_operands(&dec, isa); decode_inst_decompress(&dec, isa); decode_inst_lift_pseudo(&dec); format_inst(buf, buflen, 16, &dec); diff --git a/target/riscv/insn16.decode b/target/riscv/insn16.decode index 02c8f61b48..ccfe59f294 100644 --- a/target/riscv/insn16.decode +++ b/target/riscv/insn16.decode @@ -31,7 +31,8 @@ %imm_cb 12:s1 5:2 2:1 10:2 3:2 !function=ex_shift_1 %imm_cj 12:s1 8:1 9:2 6:1 7:1 2:1 11:1 3:3 !function=ex_shift_1 -%shimm_6bit 12:1 2:5 !function=ex_rvc_shifti +%shlimm_6bit 12:1 2:5 !function=ex_rvc_shiftli +%shrimm_6bit 12:1 2:5 !function=ex_rvc_shiftri %uimm_6bit_lq 2:4 12:1 6:1 !function=ex_shift_4 %uimm_6bit_ld 2:3 12:1 5:2 !function=ex_shift_3 %uimm_6bit_lw 2:2 12:1 4:3 !function=ex_shift_2 @@ -82,9 +83,9 @@ @c_addi16sp ... . ..... ..... .. &i imm=%imm_addi16sp rs1=2 rd=2 @c_shift ... . .. ... ..... .. \ - &shift rd=%rs1_3 rs1=%rs1_3 shamt=%shimm_6bit + &shift rd=%rs1_3 rs1=%rs1_3 shamt=%shrimm_6bit @c_shift2 ... . .. ... ..... .. \ - &shift rd=%rd rs1=%rd shamt=%shimm_6bit + &shift rd=%rd rs1=%rd shamt=%shlimm_6bit @c_andi ... . .. ... ..... .. &i imm=%imm_ci rs1=%rs1_3 rd=%rs1_3 diff --git a/target/riscv/translate.c b/target/riscv/translate.c index f8af6daa70..6eeb728462 100644 --- a/target/riscv/translate.c +++ b/target/riscv/translate.c @@ -705,10 +705,26 @@ static int ex_rvc_register(DisasContext *ctx, int reg) return 8 + reg; } -static int ex_rvc_shifti(DisasContext *ctx, int imm) +static int ex_rvc_shiftli(DisasContext *ctx, int imm) { /* For RV128 a shamt of 0 means a shift by 64. */ - return imm ? imm : 64; + if (get_ol(ctx) == MXL_RV128) { + imm = imm ? imm : 64; + } + return imm; +} + +static int ex_rvc_shiftri(DisasContext *ctx, int imm) +{ + /* + * For RV128 a shamt of 0 means a shift by 64, furthermore, for right + * shifts, the shamt is sign-extended. + */ + if (get_ol(ctx) == MXL_RV128) { + imm = imm | (imm & 32) << 1; + imm = imm ? imm : 64; + } + return imm; } /* Include the auto-generated decoder for 32 bit insn */