Hi Sirl, As you mentioned in Bugzilla (comment 13), aix_return (return in memory) svr4_return (return in register) what is the semantics of svr4gnu w.r.t. return.
On Mon, Nov 19, 2018 at 11:33 PM Franz Sirl < franz.sirl-ker...@lauterbach.com> wrote: > Am 2018-11-19 um 15:36 schrieb Lokesh Janghel: > > Hi Segher, > > > > I am building the GCC with the following configuration ( using gcc trunk > ). > > ../gcc/configure --target=powerpc-linux > > --prefix=/opt/buckeye/powerpc-linux --disable-shared --disable-threads > > --enable-languages=c --with-newlib > > > > And my assembly code (without optimization) is: > > $ cc1 -msvr4-struct-return test.c > > .LFB0: > > stwu 1,-32(1) > > .LCFI0: > > stw 31,28(1) > > .LCFI1: > > mr 31,1 > > .LCFI2: > > lis 9,.LC0@ha > > la 9,.LC0@l(9) > > lhz 10,0(9) > > lbz 9,2(9) > > sth 10,11(31) > > stb 9,13(31) > > lhz 10,11(31) > > lbz 9,13(31) > > sth 10,8(31) > > stb 9,10(31) > > li 9,0 > > lbz 10,8(31) > > rlwinm 10,10,0,24,31 > > slwi 10,10,16 > > rlwinm 9,9,0,16,7 > > or 9,9,10 > > lbz 10,9(31) > > rlwinm 10,10,0,24,31 > > slwi 10,10,8 > > rlwinm 9,9,0,24,15 > > or 9,9,10 > > lbz 10,10(31) > > rlwinm 10,10,0,24,31 > > rlwinm 9,9,0,0,23 > > or 9,9,10 > > mr 3,9 > > addi 11,31,32 > > lwz 31,-4(11) > > .LCFI3: > > mr 1,11 > > .LCFI4: > > blr > > > > > > Assembly code (with optimization -O2) is: > > $ cc1 -msvr4-struct-return -O2 test.c > > .LFB0: > > stwu 1,-32(1) > > .LCFI0: > > lis 3,0x11 > > ori 3,3,0x2233 > > addi 1,1,32 > > .LCFI1: > > blr > > > > As you mentioned assembly code in the GCC Bugzilla, I am not able to > > reproduce the issue. > > Please let me know your options used to reproduce this issue. > > Hi, > > you already reproduced the issue, according to the ABI, the code should > look like: > > .LFB0: > stwu 1,-32(1) > .LCFI0: > lis 3,0x1122 > ori 3,3,0x3300 > addi 1,1,32 > .LCFI1: > blr > > So the value being passed around should be left-aligned in the register. > > > Sirl, > > If you got the patch for this issue or will look into the issue. > > I have an unfinished patch, it misses commandline handling, testcases > and some code comments. I've attached it. > > It's unlikely I can continue to work on it anytime soon :-(. > > Franz > -- Thanks & Regards Lokesh Janghel +91-9752984749
