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HPPA Options

The following ‘-m’ options are defined for the HPPA family of computers.

-mpa-risc-1-0
Generate code for a PA 1.0 processor.

-mpa-risc-1-1
Generate code for a PA 1.1 processor.

-mjump-in-delay
Fill delay slots of function calls with unconditional jump instructions by modifying the return pointer for the function call to be the target of the conditional jump.

-mdisable-fpregs
Prevent floating point registers from being used in any manner. This is necessary for compiling kernels which perform lazy context switching of floating point registers. If you use this option and attempt to perform floating point operations, the compiler will abort.

-mdisable-indexing
Prevent the compiler from using indexing address modes. This avoids some rather obscure problems when compiling MIG generated code under MACH.

-mno-space-regs
Generate code that assumes the target has no space registers.
This allows GCC to generate faster indirect calls and use unscaled index address modes.
Such code is suitable for level 0 PA systems and kernels.

-mfast-indirect-calls
Generate code that assumes calls never cross space boundaries. This allows GCC to emit code which performs faster indirect calls.
This option will not work in the presense of shared libraries or nested functions.

-mspace
Optimize for space rather than execution time. Currently this only enables out of line function prologues and epilogues. This option is incompatible with PIC code generation and profiling.

-mlong-load-store
Generate 3-instruction load and store sequences as some-times required by the HPUX 10 linker. This is equivalent to the ‘+k’ option to the HP compilers.

-mportable-runtime
Use the portable calling conventions proposed by HP for ELF systems.

-mgas
Enable the use of assembler directives only GAS understands.

-mschedule=cpu type
Schedule code according to the constraints for the machine type cpu type. The choices for cpu type are 700 for 7 n 0 ma-chines, 7100 for 7 n 5 machines, and 7100 for 7 n 2 machines. 7100 is the default for cpu type.

Note:
The 7100LC scheduling information is incomplete and using 7100LC often leads to bad schedules. For now it’s probably best to use 7100 instead of 7100LC for the 7 n 2 machines.

-mlinker-opt
Enable the optimization pass in the HPUX linker.

Note:
This makes symbolic debugging impossible. It also triggers a bug in the HPUX 8 and HPUX 9 linkers in which they give bogus error messages when linking some programs.

-msoft-float
Generate output containing library calls for floating point.

Warning:
The requisite libraries are not available for all HPPA targets. Normally the facilities of the machine’s usual C compiler are used, but this cannot be done directly in cross-compilation. You must make your own arrangements to provide suitable library functions for cross-compilation. The embedded target hppa1.1-*-pro does provide software floating point support.

-msoft-float changes the calling convention in the output file; therefore, it is only useful if you compile all of a program with this option. In particular, you need to compile libgcc.a, the library that comes with GNU CC, with -msoft-float in order for this to work.