| Message ID | 20221020104154.4276-4-zhiwei_liu@linux.alibaba.com |
|---|---|
| State | New |
| Headers | show |
| Series | Fix some TCG RISC-V backend bugs | expand |
On 10/20/22 20:41, LIU Zhiwei wrote: > It's not clear what it is doing here. And it's wrong because bl and > al are both register, so we can't add them by an ADDI instruction. > > Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com> > --- > tcg/riscv/tcg-target.c.inc | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/tcg/riscv/tcg-target.c.inc b/tcg/riscv/tcg-target.c.inc > index bfdf2bea69..a07fd0864f 100644 > --- a/tcg/riscv/tcg-target.c.inc > +++ b/tcg/riscv/tcg-target.c.inc > @@ -705,9 +705,6 @@ static void tcg_out_addsub2(TCGContext *s, > tcg_out_opc_reg(s, OPC_SLTU, TCG_REG_TMP0, > rl, al); > } > - } else if (rl == al && rl == bl) { > - tcg_out_opc_imm(s, OPC_SLTI, TCG_REG_TMP0, al, 0); > - tcg_out_opc_reg(s, opc_addi, rl, al, bl); > } else { Removing this is incorrect; it's a simple typo for opc_add. The case being required for rl == al == bl, which the following else will treat incorrectly. r~
On 2022/10/20 19:31, Richard Henderson wrote: > On 10/20/22 20:41, LIU Zhiwei wrote: >> It's not clear what it is doing here. And it's wrong because bl and >> al are both register, so we can't add them by an ADDI instruction. >> >> Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com> >> --- >> tcg/riscv/tcg-target.c.inc | 3 --- >> 1 file changed, 3 deletions(-) >> >> diff --git a/tcg/riscv/tcg-target.c.inc b/tcg/riscv/tcg-target.c.inc >> index bfdf2bea69..a07fd0864f 100644 >> --- a/tcg/riscv/tcg-target.c.inc >> +++ b/tcg/riscv/tcg-target.c.inc >> @@ -705,9 +705,6 @@ static void tcg_out_addsub2(TCGContext *s, >> tcg_out_opc_reg(s, OPC_SLTU, TCG_REG_TMP0, >> rl, al); >> } >> - } else if (rl == al && rl == bl) { >> - tcg_out_opc_imm(s, OPC_SLTI, TCG_REG_TMP0, al, 0); >> - tcg_out_opc_reg(s, opc_addi, rl, al, bl); >> } else { > > Removing this is incorrect; it's a simple typo for opc_add. > > The case being required for rl == al == bl, which the following else > will treat incorrectly. Thanks. Get it. Zhiwei > > > r~
diff --git a/tcg/riscv/tcg-target.c.inc b/tcg/riscv/tcg-target.c.inc index bfdf2bea69..a07fd0864f 100644 --- a/tcg/riscv/tcg-target.c.inc +++ b/tcg/riscv/tcg-target.c.inc @@ -705,9 +705,6 @@ static void tcg_out_addsub2(TCGContext *s, tcg_out_opc_reg(s, OPC_SLTU, TCG_REG_TMP0, rl, al); } - } else if (rl == al && rl == bl) { - tcg_out_opc_imm(s, OPC_SLTI, TCG_REG_TMP0, al, 0); - tcg_out_opc_reg(s, opc_addi, rl, al, bl); } else { tcg_out_opc_reg(s, opc_add, rl, al, bl); tcg_out_opc_reg(s, OPC_SLTU, TCG_REG_TMP0,
It's not clear what it is doing here. And it's wrong because bl and al are both register, so we can't add them by an ADDI instruction. Signed-off-by: LIU Zhiwei <zhiwei_liu@linux.alibaba.com> --- tcg/riscv/tcg-target.c.inc | 3 --- 1 file changed, 3 deletions(-)