Re: [Qemu-devel] [PATCH v7 09/80] target/mips: Check ELPA flag only in some cases of MFHC0 and MTHC0

[Philippe Mathieu-Daudé]

On 08/06/2018 01:59 PM, Aleksandar Markovic wrote:
> From: Yongbok Kim <address@hidden>
> 
> MFHC0 and MTHC0 used to handle EntryLo0 and EntryLo1 registers only,
> and placing ELPA flag checks before switch statement were technically
> correct. However, after adding handling more registers, these checks
> should be moved to act only in cases of handling EntryLo0 and
> EntryLo1.
> 
> Reviewed-by: Aleksandar Markovic <address@hidden>
> Reviewed-by: Richard Henderson <address@hidden>
> Signed-off-by: Yongbok Kim <address@hidden>
> Signed-off-by: Aleksandar Markovic <address@hidden>

Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

> ---
>  target/mips/translate.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/target/mips/translate.c b/target/mips/translate.c
> index 841c0c8..bc1f21f 100644
> --- a/target/mips/translate.c
> +++ b/target/mips/translate.c
> @@ -4896,12 +4896,11 @@ static void gen_mfhc0(DisasContext *ctx, TCGv arg, 
> int reg, int sel)
>  {
>      const char *rn = "invalid";
>  
> -    CP0_CHECK(ctx->hflags & MIPS_HFLAG_ELPA);
> -
>      switch (reg) {
>      case 2:
>          switch (sel) {
>          case 0:
> +            CP0_CHECK(ctx->hflags & MIPS_HFLAG_ELPA);
>              gen_mfhc0_entrylo(arg, offsetof(CPUMIPSState, CP0_EntryLo0));
>              rn = "EntryLo0";
>              break;
> @@ -4912,6 +4911,7 @@ static void gen_mfhc0(DisasContext *ctx, TCGv arg, int 
> reg, int sel)
>      case 3:
>          switch (sel) {
>          case 0:
> +            CP0_CHECK(ctx->hflags & MIPS_HFLAG_ELPA);
>              gen_mfhc0_entrylo(arg, offsetof(CPUMIPSState, CP0_EntryLo1));
>              rn = "EntryLo1";
>              break;
> @@ -4964,12 +4964,11 @@ static void gen_mthc0(DisasContext *ctx, TCGv arg, 
> int reg, int sel)
>      const char *rn = "invalid";
>      uint64_t mask = ctx->PAMask >> 36;
>  
> -    CP0_CHECK(ctx->hflags & MIPS_HFLAG_ELPA);
> -
>      switch (reg) {
>      case 2:
>          switch (sel) {
>          case 0:
> +            CP0_CHECK(ctx->hflags & MIPS_HFLAG_ELPA);
>              tcg_gen_andi_tl(arg, arg, mask);
>              gen_mthc0_entrylo(arg, offsetof(CPUMIPSState, CP0_EntryLo0));
>              rn = "EntryLo0";
> @@ -4981,6 +4980,7 @@ static void gen_mthc0(DisasContext *ctx, TCGv arg, int 
> reg, int sel)
>      case 3:
>          switch (sel) {
>          case 0:
> +            CP0_CHECK(ctx->hflags & MIPS_HFLAG_ELPA);
>              tcg_gen_andi_tl(arg, arg, mask);
>              gen_mthc0_entrylo(arg, offsetof(CPUMIPSState, CP0_EntryLo1));
>              rn = "EntryLo1";
>