| Message ID | 1443627027-2193-5-git-send-email-james.hogan@imgtec.com |
|---|---|
| State | New |
| Headers | show |
On 10/01/2015 01:30 AM, James Hogan wrote: > MIPSr6 encodes JR as JALR with zero as the link register, and the pre-r6 > JR encoding is removed. Update TCG to use the new encoding when built > for r6. > > We still use the old encoding for pre-r6, so as not to confuse return > prediction stack hardware which may detect only particular encodings of > the return instruction. > > Signed-off-by: James Hogan <james.hogan@imgtec.com> > Cc: Richard Henderson <rth@twiddle.net> > Cc: Aurelien Jarno <aurelien@aurel32.net> > --- > tcg/mips/tcg-target.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/tcg/mips/tcg-target.c b/tcg/mips/tcg-target.c > index 4305af967326..0a16140b1cdb 100644 > --- a/tcg/mips/tcg-target.c > +++ b/tcg/mips/tcg-target.c > @@ -288,7 +288,7 @@ typedef enum { > OPC_SRLV = OPC_SPECIAL | 0x06, > OPC_ROTRV = OPC_SPECIAL | (0x01 << 6) | 0x06, > OPC_SRAV = OPC_SPECIAL | 0x07, > - OPC_JR = OPC_SPECIAL | 0x08, > + OPC_JR_R5 = OPC_SPECIAL | 0x08, > OPC_JALR = OPC_SPECIAL | 0x09, > OPC_MOVZ = OPC_SPECIAL | 0x0A, > OPC_MOVN = OPC_SPECIAL | 0x0B, > @@ -322,6 +322,9 @@ typedef enum { > OPC_SEH = OPC_SPECIAL3 | 0x620, > } MIPSInsn; > > +/* MIPS r6 doesn't have JR, JALR should be used instead */ > +#define OPC_JR (use_mips32r6_instructions ? OPC_JALR : OPC_JR_R5) This could be done in the enum instead of a define, but otherwise, Reviewed-by: Richard Henderson <rth@twiddle.net> r~
Hi Richard, On Thu, Oct 01, 2015 at 06:49:11AM +1000, Richard Henderson wrote: > On 10/01/2015 01:30 AM, James Hogan wrote: > > MIPSr6 encodes JR as JALR with zero as the link register, and the pre-r6 > > JR encoding is removed. Update TCG to use the new encoding when built > > for r6. > > > > We still use the old encoding for pre-r6, so as not to confuse return > > prediction stack hardware which may detect only particular encodings of > > the return instruction. > > > > Signed-off-by: James Hogan <james.hogan@imgtec.com> > > Cc: Richard Henderson <rth@twiddle.net> > > Cc: Aurelien Jarno <aurelien@aurel32.net> > > --- > > tcg/mips/tcg-target.c | 5 ++++- > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/tcg/mips/tcg-target.c b/tcg/mips/tcg-target.c > > index 4305af967326..0a16140b1cdb 100644 > > --- a/tcg/mips/tcg-target.c > > +++ b/tcg/mips/tcg-target.c > > @@ -288,7 +288,7 @@ typedef enum { > > OPC_SRLV = OPC_SPECIAL | 0x06, > > OPC_ROTRV = OPC_SPECIAL | (0x01 << 6) | 0x06, > > OPC_SRAV = OPC_SPECIAL | 0x07, > > - OPC_JR = OPC_SPECIAL | 0x08, > > + OPC_JR_R5 = OPC_SPECIAL | 0x08, > > OPC_JALR = OPC_SPECIAL | 0x09, > > OPC_MOVZ = OPC_SPECIAL | 0x0A, > > OPC_MOVN = OPC_SPECIAL | 0x0B, > > @@ -322,6 +322,9 @@ typedef enum { > > OPC_SEH = OPC_SPECIAL3 | 0x620, > > } MIPSInsn; > > > > +/* MIPS r6 doesn't have JR, JALR should be used instead */ > > +#define OPC_JR (use_mips32r6_instructions ? OPC_JALR : OPC_JR_R5) > > This could be done in the enum instead of a define, but otherwise, True, I'll do that. Thanks James > > > Reviewed-by: Richard Henderson <rth@twiddle.net> > > > r~ > >
diff --git a/tcg/mips/tcg-target.c b/tcg/mips/tcg-target.c index 4305af967326..0a16140b1cdb 100644 --- a/tcg/mips/tcg-target.c +++ b/tcg/mips/tcg-target.c @@ -288,7 +288,7 @@ typedef enum { OPC_SRLV = OPC_SPECIAL | 0x06, OPC_ROTRV = OPC_SPECIAL | (0x01 << 6) | 0x06, OPC_SRAV = OPC_SPECIAL | 0x07, - OPC_JR = OPC_SPECIAL | 0x08, + OPC_JR_R5 = OPC_SPECIAL | 0x08, OPC_JALR = OPC_SPECIAL | 0x09, OPC_MOVZ = OPC_SPECIAL | 0x0A, OPC_MOVN = OPC_SPECIAL | 0x0B, @@ -322,6 +322,9 @@ typedef enum { OPC_SEH = OPC_SPECIAL3 | 0x620, } MIPSInsn; +/* MIPS r6 doesn't have JR, JALR should be used instead */ +#define OPC_JR (use_mips32r6_instructions ? OPC_JALR : OPC_JR_R5) + /* * Type reg */
MIPSr6 encodes JR as JALR with zero as the link register, and the pre-r6 JR encoding is removed. Update TCG to use the new encoding when built for r6. We still use the old encoding for pre-r6, so as not to confuse return prediction stack hardware which may detect only particular encodings of the return instruction. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Aurelien Jarno <aurelien@aurel32.net> --- tcg/mips/tcg-target.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)