Re: [Qemu-devel] [PATCH 00/52] 680x0 instructions emulation

[Andreas Schwab]

Andreas Schwab <address@hidden> writes:

> Here is a testcase:
>
> when compiling tlink.c from the gcc sources with gcc-6 r234449 (which
> was bootstrapped in aranym):
>
> $ g++ -fno-PIE -c   -fomit-frame-pointer -O2 -DIN_GCC     -fno-exceptions 
> -fno-rtti -fasynchronous-unwind-tables -W -Wall -Wno-narrowing 
> -Wwrite-strings -Wcast-qual -Wmissing-format-attribute -Woverloaded-virtual 
> -pedantic -Wno-long-long -Wno-variadic-macros -Wno-overlength-strings -Werror 
>   -DHAVE_CONFIG_H -I. -I. -I../../gcc -I../../gcc/. -I../../gcc/../include 
> -I../../gcc/../libcpp/include  -I../../gcc/../libdecnumber 
> -I../../gcc/../libdecnumber/dpd -I../libdecnumber -I../../gcc/../libbacktrace 
>   -o tlink.o ../../gcc/tlink.c
>
> I get this difference for the generated assembler:

I have accidentially used gcc-5 for the test.  With gcc-6 as above this
is the only difference:

--- aranym/tlink.s      2016-05-06 16:45:31.924100718 +0200
+++ qemu/tlink.s        2016-05-06 16:44:54.568052423 +0200
@@ -2471,7 +2471,8 @@ _Z8do_tlinkPPcS0_:
        move.l 4(%a5),%d7
        cmp.l %d2,%d7
        jne .L329
-       btst #0,3(%a5)
+       move.b 3(%a5),%d0
+       btst #0,%d0
        jeq .L384
        move.l -14(%fp),%a1
        clr.l 4(%a1)

Andreas.

-- 
Andreas Schwab, address@hidden
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