alpha: turn -mcpu=<cpu> into -m<cpu> for the assembler all the time
If you create a toolchain with the target alphaev68-unknown-linux-gnu, gcc will use the -mcpu=ev67 by default when compiling. Some software packages (like gmp) will use this target info to decide that it may freely use assembly code that targets ev67+. The trouble comes in when trying to compile that pure assembly code. While gcc will use -mcpu=ev67 just fine, it will invoke gas without an -mev67 option, so the assembler will default to the lowest common denominator -- ev4 in this case. Inline assembly in C code is normally just peachy because gcc's assembler output will start with ".arch <cpu>" and the assembler will accept that. But if the hand coded assembly code lacks that .arch, you easily end up with errors like so: opcode `cttz' not supported for target <all> While the assembly code could/should be fixed to explicitly output the .arch directive, I think it's reasonable to expect this to work: echo 'cttz $20,$21' | gcc -x assembler -c - -o /dev/null -mcpu=ev67 This simple patch implements that, although I guess it is a bit redundant in the default case where gcc outputs .arch. Perhaps that should all be punted in favor of a specs-only approach. Considering gas respects .arch in the code over the command line, it should also make things more natural. The command line is processed in the standard/expected way -- gcc defaults the -m option while user's custom -mcpu/-Wa,-m options come after, and the guy writing the assembly code is free to use .arch to override everything else. From-SVN: r223888
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