[Bug rtl-optimization/64532] [4.9, 5 Regression] internal compiler error: Max. number of generated reload insns per insn is achieved (90)

[pangbw at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64532

--- Comment #6 from baoshan <pangbw at gmail dot com> ---
After several days study to the code, I turn to feel the code is wrong. It
seems we should use "=t" instead of "=w" for 'y' because single float register
is expected here for "vcvt.f32.s32". From the document, "w" just means  VFP
floating-point register  but not distinguishing single, double or quad float
register:
https://gcc.gnu.org/onlinedocs/gcc/Machine-Constraints.html#Machine-Constraints

The constraint letter 't' is not documented in the GCC doc, this is a issue.