gcc: MMIX Options

1 
1 3.18.27 MMIX Options
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1 These options are defined for the MMIX:
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1 '-mlibfuncs'
1 '-mno-libfuncs'
1      Specify that intrinsic library functions are being compiled,
1      passing all values in registers, no matter the size.
1 
1 '-mepsilon'
1 '-mno-epsilon'
1      Generate floating-point comparison instructions that compare with
1      respect to the 'rE' epsilon register.
1 
1 '-mabi=mmixware'
1 '-mabi=gnu'
1      Generate code that passes function parameters and return values
1      that (in the called function) are seen as registers '$0' and up, as
1      opposed to the GNU ABI which uses global registers '$231' and up.
1 
1 '-mzero-extend'
1 '-mno-zero-extend'
1      When reading data from memory in sizes shorter than 64 bits, use
1      (do not use) zero-extending load instructions by default, rather
1      than sign-extending ones.
1 
1 '-mknuthdiv'
1 '-mno-knuthdiv'
1      Make the result of a division yielding a remainder have the same
1      sign as the divisor.  With the default, '-mno-knuthdiv', the sign
1      of the remainder follows the sign of the dividend.  Both methods
1      are arithmetically valid, the latter being almost exclusively used.
1 
1 '-mtoplevel-symbols'
1 '-mno-toplevel-symbols'
1      Prepend (do not prepend) a ':' to all global symbols, so the
1      assembly code can be used with the 'PREFIX' assembly directive.
1 
1 '-melf'
1      Generate an executable in the ELF format, rather than the default
1      'mmo' format used by the 'mmix' simulator.
1 
1 '-mbranch-predict'
1 '-mno-branch-predict'
1      Use (do not use) the probable-branch instructions, when static
1      branch prediction indicates a probable branch.
1 
1 '-mbase-addresses'
1 '-mno-base-addresses'
1      Generate (do not generate) code that uses _base addresses_.  Using
1      a base address automatically generates a request (handled by the
1      assembler and the linker) for a constant to be set up in a global
1      register.  The register is used for one or more base address
1      requests within the range 0 to 255 from the value held in the
1      register.  The generally leads to short and fast code, but the
1      number of different data items that can be addressed is limited.
1      This means that a program that uses lots of static data may require
1      '-mno-base-addresses'.
1 
1 '-msingle-exit'
1 '-mno-single-exit'
1      Force (do not force) generated code to have a single exit point in
1      each function.
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