Chiradeep Vittal wrote:
>It turns out to be a compiler issue.
>We're using gcc 3.4.3 with optimization level -Os. The following program will
>generate the illegal instruction with -Os but not with -O2
> int main (int argc, char** argv)
> {
> int seq[] = {0, 1, 2};
> return 0;
> }
>The reason is that the compiler generates code with the stswi instruction
>which is not supported by the e500. Here's our compiler configuration:
>Configured with:
>/home/steve/perforce/sw/opt/crosstool/build/powerpc-8540-linux-gnu/gcc-3.4.3-glibc-2.3.2/gcc-3.4.3/configure
> --target=powerpc-8540-linux-gnu --host=i686-host_pc-linux-gnu
>--prefix=/home/steve/perforce/sw/opt/cross-compile/powerpc-8540-linux-gnu/gcc-3.4.3-glibc-2.3.2
> --with-cpu=8540 --enable-cxx-flags=-mcpu=8540
>--with-headers=/home/steve/perforce/sw/opt/cross-compile/powerpc-8540-linux-gnu/gcc-3.4.3-glibc-2.3.2/powerpc-8540-linux-gnu/include
>
>--with-local-prefix=/home/steve/perforce/sw/opt/cross-compile/powerpc-8540-linux-gnu/gcc-3.4.3-glibc-2.3.2/powerpc-8540-linux-gnu
> --disable-nls --enable-threads=posix --enable-symvers=gnu
>--enable-__cxa_atexit --enable-languages=c,c++ --enable-shared --enable-c99
>--enable-long-long
>
>Any recommendations?
>
>
Here's the patch we use to get GCC to stop generating the invalid
intructions.
Greg Weeks
--- gcc-orig/gcc/config/rs6000/rs6000.h 2003-12-08 20:57:45.000000000
-0500
+++ gcc-new/gcc/config/rs6000/rs6000.h 2004-09-15 14:23:36.680978222
-0400
@@ -550,10 +550,10 @@
#define TARGET_LONG_DOUBLE_128 (rs6000_long_double_type_size == 128)
#define TARGET_ALTIVEC_ABI rs6000_altivec_abi
#define TARGET_ALTIVEC_VRSAVE rs6000_altivec_vrsave
+#define TARGET_E500 (rs6000_cpu == PROCESSOR_PPC8540)
#define TARGET_SPE_ABI 0
#define TARGET_SPE 0
-#define TARGET_E500 0
#define TARGET_ISEL 0
#define TARGET_FPRS 1
