[dev.typeparams] cmd/compile: add arg/result register load/spill code on ARM64

Add code that loads results into registers (used in defer return
code path) and spills argument registers (used for partially lived
in-register args).

Move some code from the amd64 package to a common place.

Change-Id: I8d59b68693048fdba86e10769c4ac58de5fcfb64
Reviewed-on: https://go-review.googlesource.com/c/go/+/322851
Trust: Cherry Mui <cherryyz@google.com>
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>

2 files changed, 10 insertions, 6 deletions

diff --git a/src/cmd/compile/internal/ssagen/arch.go b/src/cmd/compile/internal/ssagen/arch.go
index 7215f42c05..957fb3e84a 100644
--- a/src/cmd/compile/internal/ssagen/arch.go
+++ b/src/cmd/compile/internal/ssagen/arch.go
@@ -42,10 +42,10 @@ type ArchInfo struct {
 	// for all values in the block before SSAGenBlock.
 	SSAGenBlock func(s *State, b, next *ssa.Block)
 
-	// LoadRegResults emits instructions that loads register-assigned results
-	// into registers. They are already in memory (PPARAMOUT nodes).
-	// Used in open-coded defer return path.
-	LoadRegResults func(s *State, f *ssa.Func)
+	// LoadRegResult emits instructions that loads register-assigned result
+	// at n+off (n is PPARAMOUT) to register reg. The result is already in
+	// memory. Used in open-coded defer return path.
+	LoadRegResult func(s *State, f *ssa.Func, t *types.Type, reg int16, n *ir.Name, off int64) *obj.Prog
 
 	// SpillArgReg emits instructions that spill reg to n+off.
 	SpillArgReg func(pp *objw.Progs, p *obj.Prog, f *ssa.Func, t *types.Type, reg int16, n *ir.Name, off int64) *obj.Prog
diff --git a/src/cmd/compile/internal/ssagen/ssa.go b/src/cmd/compile/internal/ssagen/ssa.go
index 91b0c79cd3..f59220ab8e 100644
--- a/src/cmd/compile/internal/ssagen/ssa.go
+++ b/src/cmd/compile/internal/ssagen/ssa.go
@@ -6930,8 +6930,12 @@ func genssa(f *ssa.Func, pp *objw.Progs) {
 		// recovers a panic, it will return to caller with right results.
 		// The results are already in memory, because they are not SSA'd
 		// when the function has defers (see canSSAName).
-		if f.OwnAux.ABIInfo().OutRegistersUsed() != 0 {
-			Arch.LoadRegResults(&s, f)
+		for _, o := range f.OwnAux.ABIInfo().OutParams() {
+			n := o.Name.(*ir.Name)
+			rts, offs := o.RegisterTypesAndOffsets()
+			for i := range o.Registers {
+				Arch.LoadRegResult(&s, f, rts[i], ssa.ObjRegForAbiReg(o.Registers[i], f.Config), n, offs[i])
+			}
 		}
 
 		pp.Prog(obj.ARET)