| Message ID | 20210614083800.1166166-26-richard.henderson@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | tcg: bswap improvements | expand |
Cc'ing Craig On 6/14/21 10:37 AM, Richard Henderson wrote: > There were two bugs here: (1) the required endianness was > not present in the MemOp, and (2) we were not providing a > zero-extended input to the bswap as semantics required. > > The best fix is to fold the bswap into the memory operation, > producing the desired result directly. > > Cc: Philippe Mathieu-Daudé <f4bug@amsat.org> > Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > target/mips/tcg/mxu_translate.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > > diff --git a/target/mips/tcg/mxu_translate.c b/target/mips/tcg/mxu_translate.c > index c12cf78df7..f4356432c7 100644 > --- a/target/mips/tcg/mxu_translate.c > +++ b/target/mips/tcg/mxu_translate.c > @@ -857,12 +857,8 @@ static void gen_mxu_s32ldd_s32lddr(DisasContext *ctx) > tcg_gen_ori_tl(t1, t1, 0xFFFFF000); > } > tcg_gen_add_tl(t1, t0, t1); > - tcg_gen_qemu_ld_tl(t1, t1, ctx->mem_idx, MO_SL); > + tcg_gen_qemu_ld_tl(t1, t1, ctx->mem_idx, MO_TESL ^ (sel * MO_BSWAP)); > > - if (sel == 1) { > - /* S32LDDR */ > - tcg_gen_bswap32_tl(t1, t1, TCG_BSWAP_IZ | TCG_BSWAP_OZ); > - } > gen_store_mxu_gpr(t1, XRa); > > tcg_temp_free(t0); > Acked-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
diff --git a/target/mips/tcg/mxu_translate.c b/target/mips/tcg/mxu_translate.c index c12cf78df7..f4356432c7 100644 --- a/target/mips/tcg/mxu_translate.c +++ b/target/mips/tcg/mxu_translate.c @@ -857,12 +857,8 @@ static void gen_mxu_s32ldd_s32lddr(DisasContext *ctx) tcg_gen_ori_tl(t1, t1, 0xFFFFF000); } tcg_gen_add_tl(t1, t0, t1); - tcg_gen_qemu_ld_tl(t1, t1, ctx->mem_idx, MO_SL); + tcg_gen_qemu_ld_tl(t1, t1, ctx->mem_idx, MO_TESL ^ (sel * MO_BSWAP)); - if (sel == 1) { - /* S32LDDR */ - tcg_gen_bswap32_tl(t1, t1, TCG_BSWAP_IZ | TCG_BSWAP_OZ); - } gen_store_mxu_gpr(t1, XRa); tcg_temp_free(t0);
There were two bugs here: (1) the required endianness was not present in the MemOp, and (2) we were not providing a zero-extended input to the bswap as semantics required. The best fix is to fold the bswap into the memory operation, producing the desired result directly. Cc: Philippe Mathieu-Daudé <f4bug@amsat.org> Cc: Jiaxun Yang <jiaxun.yang@flygoat.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- target/mips/tcg/mxu_translate.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) -- 2.25.1