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c75772e3f0
On platforms where long double used to have the same format as double, but later switched to a different format (alpha, s390, sparc, and powerpc), accessing the older behavior is possible and it happens via __nldbl_* functions (not on the API, but accessible from header redirection and from compat symbols). These functions write to the global flag __ldbl_is_dbl, which tells other functions that long double variables should be handled as double. This patch takes the first step towards removing this global flag and creates __vstrfmon_l_internal, which takes an explicit flags parameter. This change arguably makes the generated code slightly worse on architectures where __ldbl_is_dbl is never true; right now, on those architectures, it's a compile-time constant; after this change, the compiler could theoretically prove that __vstrfmon_l_internal was never called with a nonzero flags argument, but it would probably need LTO to do it. This is not performance critical code and I tend to think that the maintainability benefits of removing action at a distance are worth it. However, we _could_ wrap the runtime flag check with a macro that was defined to ignore its argument and always return false on architectures where __ldbl_is_dbl is never true, if people think the codegen benefits are important. Tested for powerpc and powerpc64le. |
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| aarch64 | ||
| alpha | ||
| arm | ||
| generic | ||
| gnu | ||
| hppa | ||
| htl | ||
| hurd | ||
| i386 | ||
| ia64 | ||
| ieee754 | ||
| init_array | ||
| m68k | ||
| mach | ||
| microblaze | ||
| mips | ||
| nios2 | ||
| nptl | ||
| posix | ||
| powerpc | ||
| pthread | ||
| riscv | ||
| s390 | ||
| sh | ||
| sparc | ||
| unix | ||
| wordsize-32 | ||
| wordsize-64 | ||
| x86 | ||
| x86_64 | ||