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authorFrédéric Pétrot <frederic.petrot@univ-grenoble-alpes.fr>2022-07-10 13:04:51 +0200
committerAlistair Francis <alistair.francis@wdc.com>2022-09-07 09:18:32 +0200
commit3363277525958e173b4526f9dca225e125b1a5de (patch)
tree58eb5fb7b67a6839480d710a9347e8402bf1101b /disas
parent9a1f054d5bd9acaa82b66e09309482cba9eced63 (diff)
target/riscv: fix shifts shamt value for rv128c
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 <frederic.petrot@univ-grenoble-alpes.fr> Reviewed-by: Weiwei Li <liweiwei@iscas.ac.cn> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <20220710110451.245567-1-frederic.petrot@univ-grenoble-alpes.fr> Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Diffstat (limited to 'disas')
-rw-r--r--disas/riscv.c27
1 files changed, 21 insertions, 6 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);