From 094d845edd358fc1d7e5c55dd88a4fb87480d99a Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sun, 17 May 2020 03:00:57 +0900
Subject: [PATCH] shaderir: Remove Ident

---
 internal/shaderir/glsl.go    | 12 ++++++------
 internal/shaderir/ir_test.go | 38 ++++++++++++++++++------------------
 internal/shaderir/program.go |  9 ++++-----
 3 files changed, 29 insertions(+), 30 deletions(-)

diff --git a/internal/shaderir/glsl.go b/internal/shaderir/glsl.go
index dfdc51c24..b94912705 100644
--- a/internal/shaderir/glsl.go
+++ b/internal/shaderir/glsl.go
@@ -166,7 +166,7 @@ func (p *Program) glslFunc(f *Func) []string {
 	}
 
 	var lines []string
-	lines = append(lines, fmt.Sprintf("%s %s(%s) {", p.glslType(&f.Return), f.Name, argsstr))
+	lines = append(lines, fmt.Sprintf("%s F%d(%s) {", p.glslType(&f.Return), f.Index, argsstr))
 	lines = append(lines, p.glslBlock(&f.Block, 0, idx)...)
 	lines = append(lines, "}")
 
@@ -230,12 +230,12 @@ func (p *Program) glslBlock(b *Block, level int, localVarIndex int) []string {
 		case BuiltinFuncExpr:
 			return string(e.BuiltinFunc)
 		case SwizzlingExpr:
-			if !isValidSwizzling(e.Ident) {
-				return fmt.Sprintf("?(unexpected swizzling: %s)", e.Ident)
+			if !isValidSwizzling(e.Swizzling) {
+				return fmt.Sprintf("?(unexpected swizzling: %s)", e.Swizzling)
 			}
-			return e.Ident
-		case Ident:
-			return e.Ident
+			return e.Swizzling
+		case FunctionExpr:
+			return fmt.Sprintf("F%d", e.Index)
 		case Unary:
 			var op string
 			switch e.Op {
diff --git a/internal/shaderir/ir_test.go b/internal/shaderir/ir_test.go
index c14ca9886..1b41a1171 100644
--- a/internal/shaderir/ir_test.go
+++ b/internal/shaderir/ir_test.go
@@ -100,15 +100,15 @@ func builtinFuncExpr(f BuiltinFunc) Expr {
 
 func swizzlingExpr(swizzling string) Expr {
 	return Expr{
-		Type:  SwizzlingExpr,
-		Ident: swizzling,
+		Type:      SwizzlingExpr,
+		Swizzling: swizzling,
 	}
 }
 
-func identExpr(ident string) Expr {
+func functionExpr(index int) Expr {
 	return Expr{
-		Type:  Ident,
-		Ident: ident,
+		Type:  FunctionExpr,
+		Index: index,
 	}
 }
 
@@ -200,7 +200,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 					},
 				},
 			},
@@ -212,7 +212,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 							{Main: Vec2},
@@ -235,7 +235,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 						},
@@ -258,7 +258,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 						},
@@ -285,7 +285,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 						},
@@ -326,7 +326,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 							{Main: Float},
@@ -357,7 +357,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Bool},
 							{Main: Float},
@@ -389,7 +389,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 							{Main: Float},
@@ -401,13 +401,13 @@ varying vec3 V0;`,
 							nil,
 							exprStmt(
 								callExpr(
-									identExpr("F1"),
+									functionExpr(1),
 								),
 							),
 							assignStmt(
 								varNameExpr(Local, 2),
 								callExpr(
-									identExpr("F2"),
+									functionExpr(2),
 									varNameExpr(Local, 0),
 									varNameExpr(Local, 1),
 								),
@@ -426,7 +426,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 							{Main: Float},
@@ -457,7 +457,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Vec4},
 						},
@@ -486,7 +486,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 							{Main: Float},
@@ -534,7 +534,7 @@ varying vec3 V0;`,
 			Program: Program{
 				Funcs: []Func{
 					{
-						Name: "F0",
+						Index: 0,
 						InParams: []Type{
 							{Main: Float},
 							{Main: Float},
diff --git a/internal/shaderir/program.go b/internal/shaderir/program.go
index ea04fd396..fa2d8a3c0 100644
--- a/internal/shaderir/program.go
+++ b/internal/shaderir/program.go
@@ -27,10 +27,8 @@ type Program struct {
 	structTypes []Type
 }
 
-// TODO: How to avoid the name with existing functions?
-
 type Func struct {
-	Name        string
+	Index       int
 	InParams    []Type
 	InOutParams []Type
 	OutParams   []Type
@@ -89,7 +87,8 @@ type Expr struct {
 	Int         int32
 	Float       float32
 	BuiltinFunc BuiltinFunc
-	Ident       string
+	Swizzling   string
+	Index       int
 	Op          Op
 }
 
@@ -101,7 +100,7 @@ const (
 	VarName
 	BuiltinFuncExpr
 	SwizzlingExpr
-	Ident
+	FunctionExpr
 	Unary
 	Binary
 	Selection