diff options
Diffstat (limited to 'gcc-4.9/gcc/doc/invoke.texi')
| -rw-r--r-- | gcc-4.9/gcc/doc/invoke.texi | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/gcc-4.9/gcc/doc/invoke.texi b/gcc-4.9/gcc/doc/invoke.texi index 8ecb44565..0324a8571 100644 --- a/gcc-4.9/gcc/doc/invoke.texi +++ b/gcc-4.9/gcc/doc/invoke.texi @@ -825,7 +825,8 @@ Objective-C and Objective-C++ Dialects}. @gccoptlist{-meb -mel -mno-crt0} @emph{MSP430 Options} -@gccoptlist{-msim -masm-hex -mmcu= -mcpu= -mlarge -msmall -mrelax} +@gccoptlist{-msim -masm-hex -mmcu= -mcpu= -mlarge -msmall -mrelax @gol +-mhwmult=} @emph{NDS32 Options} @gccoptlist{-mbig-endian -mlittle-endian @gol @@ -991,6 +992,7 @@ See RS/6000 and PowerPC Options. -mhard-quad-float -msoft-quad-float @gol -mstack-bias -mno-stack-bias @gol -munaligned-doubles -mno-unaligned-doubles @gol +-muser-mode -mno-user-mode @gol -mv8plus -mno-v8plus -mvis -mno-vis @gol -mvis2 -mno-vis2 -mvis3 -mno-vis3 @gol -mcbcond -mno-cbcond @gol @@ -18218,6 +18220,28 @@ This option is passed to the assembler and linker, and allows the linker to perform certain optimizations that cannot be done until the final link. +@item mhwmult= +@opindex mhwmult= +Describes the type of hardware multiply supported by the target. +Accepted values are @code{none} for no hardware multiply, @code{16bit} +for the original 16-bit-only multiply supported by early MCUs. +@code{32bit} for the 16/32-bit multiply supported by later MCUs and +@code{f5series} for the 16/32-bit multiply supported by F5-series MCUs. +A value of @code{auto} can also be given. This tells GCC to deduce +the hardware multiply support based upon the MCU name provided by the +@option{-mmcu} option. If no @option{-mmcu} option is specified then +@code{32bit} hardware multiply support is assumed. @code{auto} is the +default setting. + +Hardware multiplies are normally performed by calling a library +routine. This saves space in the generated code. When compiling at +@code{-O3} or higher however the hardware multiplier is invoked +inline. This makes for bigger, but faster code. + +The hardware multiply routines disable interrupts whilst running and +restore the previous interrupt state when they finish. This makes +them safe to use inside interrupt handlers as well as in normal code. + @end table @node NDS32 Options @@ -20908,6 +20932,14 @@ Specifying this option avoids some rare compatibility problems with code generated by other compilers. It is not the default because it results in a performance loss, especially for floating-point code. +@item -muser-mode +@itemx -mno-user-mode +@opindex muser-mode +@opindex mno-user-mode +Do not generate code that can only run in supervisor mode. This is relevant +only for the @code{casa} instruction emitted for the LEON3 processor. The +default is @option{-mno-user-mode}. + @item -mno-faster-structs @itemx -mfaster-structs @opindex mno-faster-structs |