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c33aafcd5c
GCC cannot compile the existing assembly here on ARMv7-M, claiming impossible constraints. It is actually possible to compile if the input arguments (addresses and sizes) are first moved to a high register so as not to conflict with the use of r0-r7 in ldm/stm -- this is exactly what GCC does for ARMv6, but it won't do it on ARMv7-M for some reason. We can get a result similar to the ARMv6 code by manually moving the inputs into temporaries, but the generated code is a actually a bit smaller on ARMv7-M if the r0-r7 block is shifted up to r3-r10. This only works since ARMv7-M supports the 32-bit Thumb encoding -- 16-bit Thumb can't represent an ldm/stm instruction of this type. It's worth #ifdef'ing the code because although the ARMv7-M version works on ARMv6 too, it spills a lot of registers on the stack even though register use is mostly similar. Change-Id: I9bc8b5c76e198aecfd0a0e7a2158b1c00f82c4df |
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| .. | ||
| arm | ||
| m68k | ||
| mips | ||
| asm.make | ||
| beep.c | ||
| corelock.c | ||
| ffs.c | ||
| lcd-as-memframe-24bit.c | ||
| lcd-as-memframe.c | ||
| memcpy.c | ||
| memmove.c | ||
| mempcpy.c | ||
| memset.c | ||
| memset16.c | ||
| pcm-mixer.c | ||
| SOURCES | ||
| strlen.c | ||
| thread-unix.c | ||
| thread-win32.c | ||
| thread.c | ||
| thread.h | ||