optimization/8313: gcc 3.2 on -O2 and yields bad code for unsigned short argument

[awong@cs.washington.edu]

>Number:         8313
>Category:       optimization
>Synopsis:       gcc 3.2 on -O2 and yields bad code for unsigned short argument
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          wrong-code
>Submitter-Id:   net
>Arrival-Date:   Tue Oct 22 13:56:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     Albert Wong
>Release:        unknown-1.0
>Organization:
>Environment:
gentoo linux 1.4 PPC (G4 Cube)
>Description:
This error occurs only on optimization level 2  When passing in an argument of type unsigned short = 65535, gcc3.2 on the ppc generates the code li 3,-1 which incorrectly sign extends the value in the register to a 32-bit -1 rather than a 16-bit -1.
>How-To-Repeat:
gcc -O2 test.c

./a.out

This will be an inifinite loop, though the code should terminate after 2 calls to "inf_loop".
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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