Re: [PATCH][ARM] Big Endian and Generic tuning
On 26/10/11 10:15, Richard Earnshaw wrote: Here's an updated patch that makes no generalizations. OK? Yep Committed. Andrew
Re: [PATCH][ARM] Big Endian and Generic tuning
On 25/10/11 15:16, Richard Earnshaw wrote:
The difficulty on R profile is that although BE-32 mode is obsolete,
there is a config bit that can be set to make the CPU byte-swap the
instruction stream to make it behave largely like it is running in BE-32
mode.
I think really we should be pushing the R-profile code towards having
BE-8 as the default; but to do that we really need a compiler option
that can override this behaviour (probably -mbe-[8|32]). Once we have
that option, we can fix the compiler to prefer BE-8 as there is then a
way to get back the legacy behaviour.
Here's an updated patch that makes no generalizations.
OK?
Andrew
2011-10-26 Andrew Stubbs a...@codesourcery.com
gcc/
* config/arm/bpabi.h (BE8_LINK_SPEC): Recognize generic-armv7 tuning.
--- a/gcc/config/arm/bpabi.h
+++ b/gcc/config/arm/bpabi.h
@@ -58,6 +58,7 @@
#define BE8_LINK_SPEC \
%{mbig-endian:%{march=armv7-a|mcpu=cortex-a5 \
|mcpu=cortex-a8|mcpu=cortex-a9|mcpu=cortex-a15 \
+ |mcpu=generic-armv7-a\
|march=armv7-m|mcpu=cortex-m3 \
|march=armv7e-m|mcpu=cortex-m4 \
|march=armv6-m|mcpu=cortex-m0 \
Re: [PATCH][ARM] Big Endian and Generic tuning
On 26/10/11 14:54, Andrew Stubbs wrote:
On 25/10/11 15:16, Richard Earnshaw wrote:
The difficulty on R profile is that although BE-32 mode is obsolete,
there is a config bit that can be set to make the CPU byte-swap the
instruction stream to make it behave largely like it is running in BE-32
mode.
I think really we should be pushing the R-profile code towards having
BE-8 as the default; but to do that we really need a compiler option
that can override this behaviour (probably -mbe-[8|32]). Once we have
that option, we can fix the compiler to prefer BE-8 as there is then a
way to get back the legacy behaviour.
Here's an updated patch that makes no generalizations.
OK?
Yep
R.
Andrew
be.patch
2011-10-26 Andrew Stubbs a...@codesourcery.com
gcc/
* config/arm/bpabi.h (BE8_LINK_SPEC): Recognize generic-armv7 tuning.
--- a/gcc/config/arm/bpabi.h
+++ b/gcc/config/arm/bpabi.h
@@ -58,6 +58,7 @@
#define BE8_LINK_SPEC \
%{mbig-endian:%{march=armv7-a|mcpu=cortex-a5 \
|mcpu=cortex-a8|mcpu=cortex-a9|mcpu=cortex-a15\
+ |mcpu=generic-armv7-a \
|march=armv7-m|mcpu=cortex-m3 \
|march=armv7e-m|mcpu=cortex-m4\
|march=armv6-m|mcpu=cortex-m0 \
[PATCH][ARM] Big Endian and Generic tuning
My recent patch to add -mcpu=generic-armv7-a omitted support for big
endian. This patch should solve that.
As far as I know the only this missing is the linker spec. (I have no
big-endian targets to test with.)
OK?
Andrew
2011-10-25 Andrew Stubbs a...@codesourcery.com
gcc/
* config/arm/bpabi.h (BE8_LINK_SPEC): Recognize generic-armv7 tuning.
--- a/gcc/config/arm/bpabi.h
+++ b/gcc/config/arm/bpabi.h
@@ -58,6 +58,7 @@
#define BE8_LINK_SPEC \
%{mbig-endian:%{march=armv7-a|mcpu=cortex-a5 \
|mcpu=cortex-a8|mcpu=cortex-a9|mcpu=cortex-a15 \
+ |mcpu=generic-armv7* \
|march=armv7-m|mcpu=cortex-m3 \
|march=armv7e-m|mcpu=cortex-m4 \
|march=armv6-m|mcpu=cortex-m0 \
Re: [PATCH][ARM] Big Endian and Generic tuning
On 25/10/11 11:51, Andrew Stubbs wrote:
My recent patch to add -mcpu=generic-armv7-a omitted support for big
endian. This patch should solve that.
As far as I know the only this missing is the linker spec. (I have no
big-endian targets to test with.)
OK?
Andrew
be.patch
2011-10-25 Andrew Stubbs a...@codesourcery.com
gcc/
* config/arm/bpabi.h (BE8_LINK_SPEC): Recognize generic-armv7 tuning.
--- a/gcc/config/arm/bpabi.h
+++ b/gcc/config/arm/bpabi.h
@@ -58,6 +58,7 @@
#define BE8_LINK_SPEC \
%{mbig-endian:%{march=armv7-a|mcpu=cortex-a5 \
|mcpu=cortex-a8|mcpu=cortex-a9|mcpu=cortex-a15\
+ |mcpu=generic-armv7* \
|march=armv7-m|mcpu=cortex-m3 \
|march=armv7e-m|mcpu=cortex-m4\
|march=armv6-m|mcpu=cortex-m0 \
Hmm, just thought. Shouldn't this be generic-armv7-a and not generic-armv7?
A generic armv7 implies (to me) code that will run on all variants of
armv7, which includes both R and M profiles.
R.
Re: [PATCH][ARM] Big Endian and Generic tuning
On 25/10/11 13:19, Richard Earnshaw wrote:
2011-10-25 Andrew Stubbsa...@codesourcery.com
gcc/
* config/arm/bpabi.h (BE8_LINK_SPEC): Recognize generic-armv7 tuning.
--- a/gcc/config/arm/bpabi.h
+++ b/gcc/config/arm/bpabi.h
@@ -58,6 +58,7 @@
#define BE8_LINK_SPEC \
%{mbig-endian:%{march=armv7-a|mcpu=cortex-a5 \
|mcpu=cortex-a8|mcpu=cortex-a9|mcpu=cortex-a15 \
+ |mcpu=generic-armv7*\
|march=armv7-m|mcpu=cortex-m3 \
|march=armv7e-m|mcpu=cortex-m4 \
|march=armv6-m|mcpu=cortex-m0 \
Hmm, just thought. Shouldn't this be generic-armv7-a and not generic-armv7?
A generic armv7 implies (to me) code that will run on all variants of
armv7, which includes both R and M profiles.
The actual option is indeed -mcpu=generic-armv7-a, but I thought I might
as well wildcard it since this option appears to apply to all the
profiles, and I couldn't really see why all the existing contents should
all be listed individually (I mean, this patch proves that doing so is a
maintenance burden, even if in this case it wouldn't have helped).
Having said that, I now see it doesn't list any R-profile options. Is
that because it doesn't apply, or because there are just missing?
I can certainly make this patch A-profile specific if this is wrong.
Andrew
Re: [PATCH][ARM] Big Endian and Generic tuning
On 25/10/11 13:48, Andrew Stubbs wrote:
On 25/10/11 13:19, Richard Earnshaw wrote:
2011-10-25 Andrew Stubbsa...@codesourcery.com
gcc/
* config/arm/bpabi.h (BE8_LINK_SPEC): Recognize generic-armv7 tuning.
--- a/gcc/config/arm/bpabi.h
+++ b/gcc/config/arm/bpabi.h
@@ -58,6 +58,7 @@
#define BE8_LINK_SPEC \
%{mbig-endian:%{march=armv7-a|mcpu=cortex-a5 \
|mcpu=cortex-a8|mcpu=cortex-a9|mcpu=cortex-a15 \
+ |mcpu=generic-armv7*\
|march=armv7-m|mcpu=cortex-m3 \
|march=armv7e-m|mcpu=cortex-m4 \
|march=armv6-m|mcpu=cortex-m0 \
Hmm, just thought. Shouldn't this be generic-armv7-a and not generic-armv7?
A generic armv7 implies (to me) code that will run on all variants of
armv7, which includes both R and M profiles.
The actual option is indeed -mcpu=generic-armv7-a, but I thought I might
as well wildcard it since this option appears to apply to all the
profiles, and I couldn't really see why all the existing contents should
all be listed individually (I mean, this patch proves that doing so is a
maintenance burden, even if in this case it wouldn't have helped).
Having said that, I now see it doesn't list any R-profile options. Is
that because it doesn't apply, or because there are just missing?
I can certainly make this patch A-profile specific if this is wrong.
Andrew
The difficulty on R profile is that although BE-32 mode is obsolete,
there is a config bit that can be set to make the CPU byte-swap the
instruction stream to make it behave largely like it is running in BE-32
mode.
I think really we should be pushing the R-profile code towards having
BE-8 as the default; but to do that we really need a compiler option
that can override this behaviour (probably -mbe-[8|32]). Once we have
that option, we can fix the compiler to prefer BE-8 as there is then a
way to get back the legacy behaviour.
R.
