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GCC 4.3.4 is casting my QImode vars to SImode for libcall


Hello,

In gcc4.3.4, for my architecture: 16 BITS_PER_UNIT, 1 UNIT_PER_WORD,
with INT_TYPE_SIZE = 16 and FLOAT_TYPE_SIZE = 32, then an unsigned int
is QImode and a float is HFmode.

However with:
float uitof(unsigned int x) { return x; }

I get a call to the function __floatunsihf. Shouldn't this be __floatunqihf?
Even if I provide a floatunqihf with set_conv_libfunc this is not
used. The problem with using __floatunsihf is that it is turning a
QImod into an SImode (64bits in my case) and then convert to an HFmode
(32bits). While QImode->HFmode is an extension 16bit->32bit, SImode ->
HFmode is a truncation 64bit->32bit and not ideal at all.

Any reason behind this or can I instruct GCC not to convert the
unsigned int from QImode to SImode?

Cheers,

-- 
PMatos


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