gcc 2.95.3/ARM problems comparing with negative

[Toralf Lund <toralf at procaptura dot com>]

I'm having a rather strange problem with an ARM code built with gcc 
2.95.3. Maybe I'm missing something obvious, but it looks like the wrong 
branch is taken after a comparison with a negative constant.

I have the following test

   if(position<-ZSTP_MAX_POS)


where ZSTP_MAX_POS is #defined as 250000, and "position" is an argument 
to the function containing the test. The problem is simply that if I 
pass e.g. 1 for the position argument, the test evaluates to "true" - 
according to the debugger, anyway - but surely 1 is not smaller than 
-250000? Also, the following code is generated for the test:

8013458:    e51b3014     ldr    r3, [fp, -#20]
801345c:    e3e02a3d     mvn    r2, #249856    ; 0x3d000
8013460:    e2422090     sub    r2, r2, #144    ; 0x90
8013464:    e1530002     cmp    r3, r2
8013468:    8a000017     bhi    80134cc <_SetZoomPos+0xc4>

This is followed by the "test true" code, i.e. as far as I can tell, the 
branch is supposed to be taken when the test is not true. But will it? I 
would expect "bgt" instead of "bhi" for the branch instruction, I think.

All this with gcc 2.95.3. Maybe I could upgrade, but it seems to me that 
newer versions will actually generate less efficient code...

Help, anyone?

- Toralf


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