https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100108
Bug ID: 100108 Summary: [10 Regression] powerpc: recognize 32-bit CPU as POWER9 with -misel option Product: gcc Version: 10.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target Assignee: unassigned at gcc dot gnu.org Reporter: rin at NetBSD dot org Target Milestone: --- Created attachment 50609 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=50609&action=edit Fix for this regression GCC10 wrongly recognizes CPU as POWER9 if -misel is specified, even when it is configured for 32-bit processors: % cat test.c int main(void) { return 0; } % gcc10 -misel -S test.c -o test10.S % gcc9 -misel -S test.c -o test9.S % diff -u test9.S test10.S --- test.9 2021-04-16 10:53:47.116917225 +0900 +++ test.10 2021-04-16 10:53:38.075282430 +0900 @@ -1,5 +1,5 @@ .file "test.c" - .machine ppc + .machine power9 .section ".text" .align 2 .globl main ...(snip)... This is because rs6000_machine_from_flags() assumes ISEL instructions are supported only by POWER9 and successors. However, ISEL is also implemented for 32-bit processors like e500. Please apply the attached patch to fix the problem. ---- % gcc10 -v Using built-in specs. COLLECT_GCC=/build/tools.broken/bin/powerpc--netbsd-gcc COLLECT_LTO_WRAPPER=/build/tools.broken/libexec/gcc/powerpc--netbsd/10.3.0/lto-wrapper Target: powerpc--netbsd Configured with: /usr/src/tools/gcc/../../external/gpl3/gcc/dist/configure --target=powerpc--netbsd --enable-long-long --enable-threads --with-bugurl=http://www.NetBSD.org/support/send-pr.html --with-pkgversion='NetBSD nb1 20210411' --with-system-zlib --without-isl --enable-__cxa_atexit --enable-libstdcxx-time=rt --enable-libstdcxx-threads --with-diagnostics-color=auto-if-env --with-default-libstdcxx-abi=new --with-sysroot=/build/dest/evbppc-powerpc --with-mpc=/build/tools.broken --with-mpfr=/build/tools.broken --with-gmp=/build/tools.broken --disable-nls --disable-multilib --program-transform-name='s,^,powerpc--netbsd-,' --enable-languages='c c++ objc' --prefix=/build/tools.broken Thread model: posix Supported LTO compression algorithms: zlib gcc version 10.3.0 (NetBSD nb1 20210411) ---- % gcc9 -v Using built-in specs. COLLECT_GCC=/build/tools.9/bin/powerpc--netbsd-gcc COLLECT_LTO_WRAPPER=/build/tools.9/libexec/gcc/powerpc--netbsd/9.3.0/lto-wrapper Target: powerpc--netbsd Configured with: /usr/src/tools/gcc/../../external/gpl3/gcc.old/dist/configure --target=powerpc--netbsd --enable-long-long --enable-threads --with-bugurl=http://www.NetBSD.org/support/send-pr.html --with-pkgversion='NetBSD nb1 20200907' --with-system-zlib --without-isl --enable-__cxa_atexit --enable-libstdcxx-time=rt --enable-libstdcxx-threads --with-diagnostics-color=auto-if-env --with-default-libstdcxx-abi=new --with-sysroot=/build/dest/evbppc-powerpc --with-mpc=/build/tools.9 --with-mpfr=/build/tools.9 --with-gmp=/build/tools.9 --disable-nls --disable-multilib --program-transform-name='s,^,powerpc--netbsd-,' --enable-languages='c c++ objc' --prefix=/build/tools.9 Thread model: posix gcc version 9.3.0 (NetBSD nb1 20200907)