Hi,
DSP instructions are optional for Arm Cortex-M33, yet its -mcpu option
does not allow +nodsp. Users are thus left with using
-march=armv8-m.main -mtune=cortex-m33. This patch allows +nodsp to
-mcpu=cortex-m33.
ChangeLog entry is as follows:
*** gcc/ChangeLog ***
2017-10-11 Thomas Preud'homme <thomas.preudho...@arm.com>
* config/arm/arm-cpus.in (cortex-m33): Add nodsp option.
* doc/invoke.texi: Document +nodsp as a valid extension for
-mcpu=cortex-m33.
Tested by building an arm-none-eabi GCC cross-compiler and checking that
__ARM_FEATURE_DSP is *not* defined when invoked with
-mcpu=cortex-m33+nodsp.
Is this ok for trunk?
Best regards,
Thomas
diff --git a/gcc/config/arm/arm-cpus.in b/gcc/config/arm/arm-cpus.in
index 07de4c9375ba7a0df0d8bd00385e54a4042e5264..25fc429a8338e433b9fcd0ee385ff127423494c2 100644
--- a/gcc/config/arm/arm-cpus.in
+++ b/gcc/config/arm/arm-cpus.in
@@ -1516,6 +1516,7 @@ begin cpu cortex-m33
architecture armv8-m.main+dsp
fpu fpv5-sp-d16
option nofp remove ALL_FP
+ option nodsp remove armv7em
costs v7m
end cpu cortex-m33
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 9ad1fb339babe2ce8f45ecac2fa93d7b9ae5fd30..722d5cc2c0a020906e6df3260822cdd268245082 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -15803,6 +15803,9 @@ Permissible names for this option are the same as those for
The following extension options are common to the listed CPUs:
@table @samp
+@item +nodsp
+Disable the DSP instructions on @samp{cortex-m33}.
+
@item +nofp
Disables the floating-point instructions on @samp{arm9e},
@samp{arm946e-s}, @samp{arm966e-s}, @samp{arm968e-s}, @samp{arm10e},
