| Message ID | 1313504053-27873-3-git-send-email-dave.martin@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 16 Aug 2011, Dave Martin wrote: > When testing whether a Thumb-2 instruction is 32 bits long or not, > the masking done in order to test bits 11-15 of the first > instruction halfword won't affect the result of the comparison, so > remove it. > > Signed-off-by: Dave Martin <dave.martin@linaro.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> > --- > arch/arm/kernel/entry-armv.S | 6 ++---- > 1 files changed, 2 insertions(+), 4 deletions(-) > > diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S > index a87cbf8..b7236d4 100644 > --- a/arch/arm/kernel/entry-armv.S > +++ b/arch/arm/kernel/entry-armv.S > @@ -262,8 +262,7 @@ __und_svc: > ldr r0, [r4, #-4] > #else > ldrh r0, [r4, #-2] @ Thumb instruction at LR - 2 > - and r9, r0, #0xf800 > - cmp r9, #0xe800 @ 32-bit instruction if xx >= 0 > + cmp r0, #0xe800 @ 32-bit instruction if xx >= 0 > ldrhhs r9, [r4] @ bottom 16 bits > orrhs r0, r9, r0, lsl #16 > #endif > @@ -445,8 +444,7 @@ __und_usr: > ARM( ldrht r5, [r4], #2 ) > THUMB( ldrht r5, [r4] ) > THUMB( add r4, r4, #2 ) > - and r0, r5, #0xf800 @ mask bits 111x x... .... .... > - cmp r0, #0xe800 @ 32bit instruction if xx != 0 > + cmp r5, #0xe800 @ 32bit instruction if xx != 0 > blo __und_usr_unknown > 3: ldrht r0, [r4] > add r2, r2, #2 @ r2 is PC + 2, make it PC + 4 > -- > 1.7.4.1 >
On Tue, Aug 16, 2011 at 12:17:35PM -0400, Nicolas Pitre wrote: > On Tue, 16 Aug 2011, Dave Martin wrote: > > > When testing whether a Thumb-2 instruction is 32 bits long or not, > > the masking done in order to test bits 11-15 of the first > > instruction halfword won't affect the result of the comparison, so > > remove it. > > > > Signed-off-by: Dave Martin <dave.martin@linaro.org> > > Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> > Thanks ---Dave > > > --- > > arch/arm/kernel/entry-armv.S | 6 ++---- > > 1 files changed, 2 insertions(+), 4 deletions(-) > > > > diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S > > index a87cbf8..b7236d4 100644 > > --- a/arch/arm/kernel/entry-armv.S > > +++ b/arch/arm/kernel/entry-armv.S > > @@ -262,8 +262,7 @@ __und_svc: > > ldr r0, [r4, #-4] > > #else > > ldrh r0, [r4, #-2] @ Thumb instruction at LR - 2 > > - and r9, r0, #0xf800 > > - cmp r9, #0xe800 @ 32-bit instruction if xx >= 0 > > + cmp r0, #0xe800 @ 32-bit instruction if xx >= 0 > > ldrhhs r9, [r4] @ bottom 16 bits > > orrhs r0, r9, r0, lsl #16 > > #endif > > @@ -445,8 +444,7 @@ __und_usr: > > ARM( ldrht r5, [r4], #2 ) > > THUMB( ldrht r5, [r4] ) > > THUMB( add r4, r4, #2 ) > > - and r0, r5, #0xf800 @ mask bits 111x x... .... .... > > - cmp r0, #0xe800 @ 32bit instruction if xx != 0 > > + cmp r5, #0xe800 @ 32bit instruction if xx != 0 > > blo __und_usr_unknown > > 3: ldrht r0, [r4] > > add r2, r2, #2 @ r2 is PC + 2, make it PC + 4 > > -- > > 1.7.4.1 > >
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S index a87cbf8..b7236d4 100644 --- a/arch/arm/kernel/entry-armv.S +++ b/arch/arm/kernel/entry-armv.S @@ -262,8 +262,7 @@ __und_svc: ldr r0, [r4, #-4] #else ldrh r0, [r4, #-2] @ Thumb instruction at LR - 2 - and r9, r0, #0xf800 - cmp r9, #0xe800 @ 32-bit instruction if xx >= 0 + cmp r0, #0xe800 @ 32-bit instruction if xx >= 0 ldrhhs r9, [r4] @ bottom 16 bits orrhs r0, r9, r0, lsl #16 #endif @@ -445,8 +444,7 @@ __und_usr: ARM( ldrht r5, [r4], #2 ) THUMB( ldrht r5, [r4] ) THUMB( add r4, r4, #2 ) - and r0, r5, #0xf800 @ mask bits 111x x... .... .... - cmp r0, #0xe800 @ 32bit instruction if xx != 0 + cmp r5, #0xe800 @ 32bit instruction if xx != 0 blo __und_usr_unknown 3: ldrht r0, [r4] add r2, r2, #2 @ r2 is PC + 2, make it PC + 4
When testing whether a Thumb-2 instruction is 32 bits long or not, the masking done in order to test bits 11-15 of the first instruction halfword won't affect the result of the comparison, so remove it. Signed-off-by: Dave Martin <dave.martin@linaro.org> --- arch/arm/kernel/entry-armv.S | 6 ++---- 1 files changed, 2 insertions(+), 4 deletions(-)