From faafa00e403dd940fba75f0f79649b07c8e50461 Mon Sep 17 00:00:00 2001
From: Michael McLoughlin <mmcloughlin@gmail.com>
Date: Mon, 3 Dec 2018 20:40:43 -0800
Subject: [PATCH] pass: test for liveness

---
 build/context.go  |  5 ++-
 pass/reg_test.go  | 90 +++++++++++++++++++++++++++++++++++++++++++++++
 reg/collection.go | 33 +++++++++++++++++
 reg/types.go      | 14 +++++---
 4 files changed, 136 insertions(+), 6 deletions(-)
 create mode 100644 pass/reg_test.go
 create mode 100644 reg/collection.go

diff --git a/build/context.go b/build/context.go
index 3744b9b..ea86117 100644
--- a/build/context.go
+++ b/build/context.go
@@ -6,17 +6,20 @@ import (
 	"log"
 
 	"github.com/mmcloughlin/avo"
+	"github.com/mmcloughlin/avo/reg"
 )
 
 type Context struct {
 	file     *avo.File
 	function *avo.Function
 	errs     []error
+	reg.Collection
 }
 
 func NewContext() *Context {
 	return &Context{
-		file: avo.NewFile(),
+		file:       avo.NewFile(),
+		Collection: *reg.NewCollection(),
 	}
 }
 
diff --git a/pass/reg_test.go b/pass/reg_test.go
new file mode 100644
index 0000000..d4dd542
--- /dev/null
+++ b/pass/reg_test.go
@@ -0,0 +1,90 @@
+package pass_test
+
+import (
+	"testing"
+
+	"github.com/mmcloughlin/avo/reg"
+
+	"github.com/mmcloughlin/avo/pass"
+
+	"github.com/mmcloughlin/avo"
+	"github.com/mmcloughlin/avo/build"
+	"github.com/mmcloughlin/avo/operand"
+)
+
+func TestLivenessBasic(t *testing.T) {
+	// Build: a = 1, b = 2, a = a+b
+	ctx := build.NewContext()
+	ctx.Function("add")
+	a := ctx.GP64v()
+	b := ctx.GP64v()
+	ctx.MOVQ(operand.Imm(1), a)
+	ctx.MOVQ(operand.Imm(2), b)
+	ctx.ADDQ(a, b)
+
+	AssertLiveness(t, ctx,
+		[][]reg.Register{
+			{},
+			{a},
+			{a, b},
+		},
+		[][]reg.Register{
+			{a},
+			{a, b},
+			{},
+		},
+	)
+}
+
+func AssertLiveness(t *testing.T, ctx *build.Context, in, out [][]reg.Register) {
+	fn := ConstructLiveness(t, ctx)
+	is := fn.Instructions()
+
+	if len(in) != len(is) || len(out) != len(is) {
+		t.Fatalf("%d instructions: %d/%d in/out expectations", len(is), len(in), len(out))
+	}
+
+	for idx, i := range is {
+		AssertRegistersMatchSet(t, in[idx], i.LiveIn)
+		AssertRegistersMatchSet(t, out[idx], i.LiveOut)
+	}
+}
+
+func AssertRegistersMatchSet(t *testing.T, rs []reg.Register, s map[reg.ID]bool) {
+	if len(rs) != len(s) {
+		t.Fatalf("size mismatch")
+	}
+	for _, r := range rs {
+		if _, found := s[r.ID()]; !found {
+			t.Fatalf("missing register ID %v", r.ID())
+		}
+	}
+}
+
+func ConstructLiveness(t *testing.T, ctx *build.Context) *avo.Function {
+	f, errs := ctx.Result()
+	if errs != nil {
+		for _, err := range errs {
+			t.Error(err)
+		}
+		t.FailNow()
+	}
+
+	if len(f.Functions) != 1 {
+		t.Fatalf("expect 1 function")
+	}
+	fn := f.Functions[0]
+
+	passes := []func(*avo.Function) error{
+		pass.LabelTarget,
+		pass.CFG,
+		pass.Liveness,
+	}
+	for _, p := range passes {
+		if err := p(fn); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	return fn
+}
diff --git a/reg/collection.go b/reg/collection.go
new file mode 100644
index 0000000..70ca8c6
--- /dev/null
+++ b/reg/collection.go
@@ -0,0 +1,33 @@
+package reg
+
+type Collection struct {
+	vid map[Kind]VID
+}
+
+func NewCollection() *Collection {
+	return &Collection{
+		vid: map[Kind]VID{},
+	}
+}
+
+func (c *Collection) VirtualRegister(k Kind, s Size) Virtual {
+	vid := c.vid[k]
+	c.vid[k]++
+	return NewVirtual(vid, k, s)
+}
+
+func (c *Collection) GP8v() Virtual { return c.GPv(B8) }
+
+func (c *Collection) GP16v() Virtual { return c.GPv(B16) }
+
+func (c *Collection) GP32v() Virtual { return c.GPv(B32) }
+
+func (c *Collection) GP64v() Virtual { return c.GPv(B64) }
+
+func (c *Collection) GPv(s Size) Virtual { return c.VirtualRegister(GP, s) }
+
+func (c *Collection) Xv() Virtual { return c.VirtualRegister(SSEAVX, B128) }
+
+func (c *Collection) Yv() Virtual { return c.VirtualRegister(SSEAVX, B256) }
+
+func (c *Collection) Zv() Virtual { return c.VirtualRegister(SSEAVX, B512) }
diff --git a/reg/types.go b/reg/types.go
index 1400a0c..ed455ee 100644
--- a/reg/types.go
+++ b/reg/types.go
@@ -38,11 +38,7 @@ func (f *Family) define(s Spec, id PID, name string) Physical {
 }
 
 func (f *Family) Virtual(id VID, s Size) Virtual {
-	return virtual{
-		id:   id,
-		kind: f.Kind,
-		Size: s,
-	}
+	return NewVirtual(id, f.Kind, s)
 }
 
 type private interface {
@@ -74,6 +70,14 @@ type virtual struct {
 	Size
 }
 
+func NewVirtual(id VID, k Kind, s Size) Virtual {
+	return virtual{
+		id:   id,
+		kind: k,
+		Size: s,
+	}
+}
+
 func (v virtual) VirtualID() VID { return v.id }
 func (v virtual) Kind() Kind     { return v.kind }