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I'd like to remove -many from the options passed by default to the assembler, on the grounds that a gcc bug in instruction selection (eg. emitting a power9 insn for -mcpu=power8) is better found at assembly time than run time. For now, just do this when --enable-checking or gcc is not a release. This patch also emits .machine assembler directives for ELF targets when functions are compiled for different cpus via attributes or pragmas. That's necessary when the initial -m<cpu> option passed to the assembler doesn't enable the superset of all opcodes emitted, as seen by a failure of gcc.target/powerpc/clone2.c without .machine when building gcc for power8. rs6000_machine_from_flags deliberately uses ISA_2_4_MASKS rather than ISA_2_2_MASKS for power5 because "friz" and other similar instructions enabled by gcc with TARGET_FPRND are enabled in gas by "-mpower5". (gas -mpower5 supports power5+ too.) rs6000-cpus.def puts OPTION_MASK_FPRND in ISA_2_4_MASKS, so ISA_2_4_MASKS is the one to use in deciding to pass "-mpower5" to gas. O3-pr70130.c also failed on an earlier version of this patch (when only testing one ISA bit to determine .machine). This is a test for a power7 vector bug, but on power8 hw check_vect_support_and_set_flags passes -mpower8-vector which means the test isn't exercising the original bug exactly. I reckon that is wrong, and similary for other vector testcases that ask for a specific cpu. I've fixed it here by explicitly passing -mno-power8-vector and similar vector options. * config/rs6000/rs6000.h (ASM_OPT_ANY): Define. (ASM_CPU_SPEC): Conditionally add -many. * config/rs6000/rs6000.c (rs6000_machine): New static var. (rs6000_machine_from_flags, emit_asm_machine): New functions.. (rs6000_file_start): ..extracted from here, and modified to test all ISA bits. (rs6000_output_function_prologue): Emit .machine as necessary. * testsuite/gcc.target/powerpc/ppc32-abi-dfp-1.c: Don't use power mnemonics. * testsuite/gcc.dg/vect/O3-pr70130.c: Disable default options added by check_vect_support_and_set_flags. * testsuite/gcc.dg/vect/pr48765.c: Likewise. * testsuite/gfortran.dg/vect/pr45714-b.f: Likewise. From-SVN: r271500
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