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

[Andreas Schwab]

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:

--- aranym/tlink.s      2016-05-06 16:19:02.377982900 +0200
+++ qemu/tlink.s        2016-05-06 16:18:26.385935256 +0200
@@ -2202,12 +2202,12 @@ _Z8do_tlinkPPcS0_:
        move.l ldout,-(%sp)
        move.l %d6,-(%sp)
        pea .LC23
-       jsr _Z15collect_executePKcPPcS0_S0_ib
+       move.l #_Z15collect_executePKcPPcS0_S0_ib,%d4
+       move.l %d4,%a1
+       jsr (%a1)
        move.l %a0,-(%sp)
        pea .LC23
-       move.l #_Z12collect_waitPKcP7pex_obj,%d4
-       move.l %d4,%a0
-       jsr (%a0)
+       jsr _Z12collect_waitPKcP7pex_obj
        move.l %d0,%d3
        lea (28,%sp),%sp
        clr.l (%sp)
@@ -2416,7 +2416,8 @@ _Z8do_tlinkPPcS0_:
        move.l 4(%a5),%d0
        cmp.l %d2,%d0
        jne .L327
-       btst #0,3(%a5)
+       move.b 3(%a5),%d0
+       btst #0,%d0
        jeq .L382
        clr.l 4(%a0)
        move.l %d2,%d0
@@ -2489,11 +2490,11 @@ _Z8do_tlinkPPcS0_:
        move.l ldout,-(%sp)
        move.l %d6,-(%sp)
        pea .LC23
-       jsr _Z15collect_executePKcPPcS0_S0_ib
+       move.l %d4,%a1
+       jsr (%a1)
        move.l %a0,-(%sp)
        pea .LC23
-       move.l %d4,%a0
-       jsr (%a0)
+       jsr _Z12collect_waitPKcP7pex_obj
        move.l %d0,%d3
        lea (32,%sp),%sp
        jne .L387
@@ -2562,11 +2563,11 @@ _Z8do_tlinkPPcS0_:
        move.l ldout,-(%sp)
        move.l %d6,-(%sp)
        pea .LC23
-       jsr _Z15collect_executePKcPPcS0_S0_ib
+       move.l %d4,%a1
+       jsr (%a1)
        move.l %a0,-(%sp)
        pea .LC23
-       move.l %d4,%a0
-       jsr (%a0)
+       jsr _Z12collect_waitPKcP7pex_obj
        move.l %d0,%d3
        lea (32,%sp),%sp
        jeq .L368

Andreas.

-- 
Andreas Schwab, address@hidden
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