https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97535
--- Comment #1 from Icenowy Zheng <icenowy at aosc dot io> --- The problem is found to be trying to expand a memcpy() call with fixed length 2181038080. Handling of memcpy() expansion seem to be corrupted when len >= 2147483648. The length is mod with 2147483648, and then forced to expand. When a test program that contains a call to memcpy() with len 2147483648 is tried, it is "expanded" to nothing. The problematic thing seems to be aarch64_expand_cpymem() in master at config/aarch64/aarch64.c (aarch64_expand_movmem() in GCC 9), in which the variable n is declared with `int` (a 32-bit signed integer on both AArch64 LP64 and x86-64). Modify it to HOST_WIDE_INT seems to fix the problem.
