From f8f68a4e9f5c8d8b626aa08bd86e80c5095419c6 Mon Sep 17 00:00:00 2001
From: Egon Elbre <egonelbre@gmail.com>
Date: Sat, 2 Jul 2022 16:39:16 +0300
Subject: [PATCH] internal/ops: optimize Decode

Using clean struct creation creates a lot of temporary variables in
assembly. Inline the assignments, which generates less code.

Signed-off-by: Egon Elbre <egonelbre@gmail.com>
---
 internal/ops/ops.go    | 21 ++++++---------------
 internal/ops/reader.go | 27 ++++++++-------------------
 2 files changed, 14 insertions(+), 34 deletions(-)

diff --git a/internal/ops/ops.go b/internal/ops/ops.go
index abdcd87b..fff43ad3 100644
--- a/internal/ops/ops.go
+++ b/internal/ops/ops.go
@@ -168,21 +168,12 @@ func (op *ClipOp) Decode(data []byte) {
 	}
 	data = data[:TypeClipLen]
 	bo := binary.LittleEndian
-	r := image.Rectangle{
-		Min: image.Point{
-			X: int(int32(bo.Uint32(data[1:]))),
-			Y: int(int32(bo.Uint32(data[5:]))),
-		},
-		Max: image.Point{
-			X: int(int32(bo.Uint32(data[9:]))),
-			Y: int(int32(bo.Uint32(data[13:]))),
-		},
-	}
-	*op = ClipOp{
-		Bounds:  r,
-		Outline: data[17] == 1,
-		Shape:   Shape(data[18]),
-	}
+	op.Bounds.Min.X = int(int32(bo.Uint32(data[1:])))
+	op.Bounds.Min.Y = int(int32(bo.Uint32(data[5:])))
+	op.Bounds.Max.X = int(int32(bo.Uint32(data[9:])))
+	op.Bounds.Max.Y = int(int32(bo.Uint32(data[13:])))
+	op.Outline = data[17] == 1
+	op.Shape = Shape(data[18])
 }
 
 func Reset(o *Ops) {
diff --git a/internal/ops/reader.go b/internal/ops/reader.go
index fbfc7f70..7e212dfb 100644
--- a/internal/ops/reader.go
+++ b/internal/ops/reader.go
@@ -165,14 +165,8 @@ func (op *opMacroDef) decode(data []byte) {
 	}
 	bo := binary.LittleEndian
 	data = data[:TypeMacroLen]
-	dataIdx := int(int32(bo.Uint32(data[1:])))
-	refsIdx := int(int32(bo.Uint32(data[5:])))
-	*op = opMacroDef{
-		endpc: PC{
-			data: dataIdx,
-			refs: refsIdx,
-		},
-	}
+	op.endpc.data = int(int32(bo.Uint32(data[1:])))
+	op.endpc.refs = int(int32(bo.Uint32(data[5:])))
 }
 
 func (m *macroOp) decode(data []byte, refs []interface{}) {
@@ -181,15 +175,10 @@ func (m *macroOp) decode(data []byte, refs []interface{}) {
 	}
 	bo := binary.LittleEndian
 	data = data[:TypeCallLen]
-	*m = macroOp{
-		ops: refs[0].(*Ops),
-		start: PC{
-			data: int(int32(bo.Uint32(data[1:]))),
-			refs: int(int32(bo.Uint32(data[5:]))),
-		},
-		end: PC{
-			data: int(int32(bo.Uint32(data[9:]))),
-			refs: int(int32(bo.Uint32(data[13:]))),
-		},
-	}
+
+	m.ops = refs[0].(*Ops)
+	m.start.data = int(int32(bo.Uint32(data[1:])))
+	m.start.refs = int(int32(bo.Uint32(data[5:])))
+	m.end.data = int(int32(bo.Uint32(data[9:])))
+	m.end.refs = int(int32(bo.Uint32(data[13:])))
 }