On Thu, Oct 25, 2018 at 7:12 AM Umesh Kalappa <umesh.kalap...@gmail.com> wrote: > > Hi All, > > For the below C code > > Test.u32pt = u32PtLen; > Test.u32pn = u32PtCnt; > Test.pstpk = pstPt; > Test.psteo = pstEgrInfo; > Test.e = 1; > Test.pstfi = pstFi ; > > return foo(&Test, AclAction); > > where "Test" is the struct type . > > the generated code for mips (with -fno-delayed-branch) : > > Test.u32pt = u32PtLen; > 370: afb50084 sw s5,132(sp) > Test.u32pn = u32PtCnt; > 374: afb60080 sw s6,128(sp) > Test.pstpk = pstPt; > Test.psteo = pstEgrInfo; > Test.e = 1; > Test.pstfi = pstFi ; > > return foo(&Test, AclAction) > 378: 0c000000 jal 0 <FSVC_Egr_L4ACLfoo> > 37c: 00000000 nop > > with -fdelayed-branch(gcc 4.8.1) the generated code is > > Test.u32pt = u32PtLen; > 370: afb50084 sw s5,132(sp) > Test.pstpk = pstPt; > Test.psteo = pstEgrInfo; > Test.e = 1; > Test.pstfi = pstFi ; > > return foo(&Test, AclAction) > 378: 0c000000 jal 0 <FSVC_Egr_L4ACLfoo> > Test.u32pn = u32PtCnt; > 374: afb60080 sw s6,128(sp) > > can filler place the "sw s6,128(sp)" in the delay slot ,is > that legal and if not why it so ?
Yes it is legal as stores to the stack don't "trap" in normal cases. Thanks, Andrew > > Thank you > ~Umesh
