cmd/compile: request r12 for indirect calls on ppc64le

On ppc64le, functions compiled with -shared expect r12 to
hold the function's address for indirect calls. Previously
this was enforced by generating a move instruction if the
address wasn't already in r12. This change avoids that extra
move by requesting r12 in the CALL ops that do indirect calls.

As a result of adding support for plugins on ppc64le, it was
discovered that there would be more cases where this extra
move was needed, so this seemed like a better solution.

Updates #20756

Change-Id: I6770885a46990f78c6d2902a715dcdaa822192a1
Reviewed-on: https://go-review.googlesource.com/62890
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This commit is contained in:
Lynn Boger 2017-09-11 10:39:24 -04:00
parent 818353022e
commit b74b43de68
4 changed files with 11 additions and 25 deletions

View file

@ -128,8 +128,9 @@ func init() {
// cr = buildReg("CR")
// ctr = buildReg("CTR")
// lr = buildReg("LR")
tmp = buildReg("R31")
ctxt = buildReg("R11")
tmp = buildReg("R31")
ctxt = buildReg("R11")
callptr = buildReg("R12")
// tls = buildReg("R13")
gp01 = regInfo{inputs: nil, outputs: []regMask{gp}}
gp11 = regInfo{inputs: []regMask{gp | sp | sb}, outputs: []regMask{gp}}
@ -320,8 +321,8 @@ func init() {
{name: "MOVDconvert", argLength: 2, reg: gp11, asm: "MOVD"},
{name: "CALLstatic", argLength: 1, reg: regInfo{clobbers: callerSave}, aux: "SymOff", clobberFlags: true, call: true, symEffect: "None"}, // call static function aux.(*obj.LSym). arg0=mem, auxint=argsize, returns mem
{name: "CALLclosure", argLength: 3, reg: regInfo{inputs: []regMask{gp | sp, ctxt, 0}, clobbers: callerSave}, aux: "Int64", clobberFlags: true, call: true}, // call function via closure. arg0=codeptr, arg1=closure, arg2=mem, auxint=argsize, returns mem
{name: "CALLinter", argLength: 2, reg: regInfo{inputs: []regMask{gp}, clobbers: callerSave}, aux: "Int64", clobberFlags: true, call: true}, // call fn by pointer. arg0=codeptr, arg1=mem, auxint=argsize, returns mem
{name: "CALLclosure", argLength: 3, reg: regInfo{inputs: []regMask{callptr, ctxt, 0}, clobbers: callerSave}, aux: "Int64", clobberFlags: true, call: true}, // call function via closure. arg0=codeptr, arg1=closure, arg2=mem, auxint=argsize, returns mem
{name: "CALLinter", argLength: 2, reg: regInfo{inputs: []regMask{callptr}, clobbers: callerSave}, aux: "Int64", clobberFlags: true, call: true}, // call fn by pointer. arg0=codeptr, arg1=mem, auxint=argsize, returns mem
// large or unaligned zeroing
// arg0 = address of memory to zero (in R3, changed as side effect)