[dev.ssa] cmd/compile: start arguments as spilled

Declare a function's arguments as having already been
spilled so their use just requires a restore.

Allow spill locations to be portions of larger objects the stack.
Required to load portions of compound input arguments.

Rename the memory input to InputMem.  Use Arg for the
pre-spilled argument values.

Change-Id: I8fe2a03ffbba1022d98bfae2052b376b96d32dda
Reviewed-on: https://go-review.googlesource.com/16536
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/src/cmd/compile/internal/ssa/print.go b/src/cmd/compile/internal/ssa/print.go
index 192dc83b39..b61e6f1cc7 100644
--- a/src/cmd/compile/internal/ssa/print.go
+++ b/src/cmd/compile/internal/ssa/print.go
@@ -28,6 +28,7 @@ type funcPrinter interface {
 	value(v *Value, live bool)
 	startDepCycle()
 	endDepCycle()
+	named(n LocalSlot, vals []*Value)
 }
 
 type stringFuncPrinter struct {
@@ -73,6 +74,10 @@ func (p stringFuncPrinter) startDepCycle() {
 
 func (p stringFuncPrinter) endDepCycle() {}
 
+func (p stringFuncPrinter) named(n LocalSlot, vals []*Value) {
+	fmt.Fprintf(p.w, "name %s: %v\n", n.Name(), vals)
+}
+
 func fprintFunc(p funcPrinter, f *Func) {
 	reachable, live := findlive(f)
 	p.header(f)
@@ -136,4 +141,7 @@ func fprintFunc(p funcPrinter, f *Func) {
 
 		p.endBlock(b)
 	}
+	for name, vals := range f.NamedValues {
+		p.named(name, vals)
+	}
 }