From f05efb749d4adafeed6e0a7cfb112cd76bdc1b14 Mon Sep 17 00:00:00 2001
From: Sasha Koshka <sashakoshka@tebibyte.media>
Date: Sun, 21 Apr 2024 00:19:33 -0400
Subject: [PATCH] Generator generates constants

---
 generator/constant_test.go        | 93 +++++++++++++++++++++++++++++++
 generator/expression-multiplex.go |  8 +++
 generator/expression.go           |  7 +++
 3 files changed, 108 insertions(+)
 create mode 100644 generator/constant_test.go

diff --git a/generator/constant_test.go b/generator/constant_test.go
new file mode 100644
index 0000000..56dbb13
--- /dev/null
+++ b/generator/constant_test.go
@@ -0,0 +1,93 @@
+package generator
+
+import "testing"
+
+func TestConstantValueSpecified (test *testing.T) {
+testString (test,
+`%"0zNZN147MN2wzMAQ6NS2dQ==::E" = type i64
+define void @"0zNZN147MN2wzMAQ6NS2dQ==::f"() {
+0:
+	%1 = call i64 @"0zNZN147MN2wzMAQ6NS2dQ==::plus4"(i64 2)
+	ret void
+}
+define i64 @"0zNZN147MN2wzMAQ6NS2dQ==::plus4"(%"0zNZN147MN2wzMAQ6NS2dQ==::E" %e) {
+0:
+	%1 = alloca %"0zNZN147MN2wzMAQ6NS2dQ==::E"
+	store %"0zNZN147MN2wzMAQ6NS2dQ==::E" %e, ptr %1
+	%2 = load %"0zNZN147MN2wzMAQ6NS2dQ==::E", ptr %1
+	switch %"0zNZN147MN2wzMAQ6NS2dQ==::E" %2, label %8 [
+		%"0zNZN147MN2wzMAQ6NS2dQ==::E" 1, label %5
+		%"0zNZN147MN2wzMAQ6NS2dQ==::E" 2, label %6
+		%"0zNZN147MN2wzMAQ6NS2dQ==::E" 3, label %7
+	]
+3:
+	%4 = phi i64 [ 5, %5 ], [ 6, %6 ], [ 7, %7 ], [ -1, %8 ]
+	ret i64 %4
+5:
+	br label %3
+6:
+	br label %3
+7:
+	br label %3
+8:
+	br label %3
+}
+`,
+`
+E: Int
+| one   = 1
+| two   = 2
+| three = 3
+
+[plus4 e:E]:Int = switch e
+	| E.one   5
+	| E.two   6
+	| E.three 7
+	*        -1
+[f] = [plus4 E.two]
+`)}
+
+func TestConstantValueUnspecified (test *testing.T) {
+testString (test,
+`%"0zNZN147MN2wzMAQ6NS2dQ==::E" = type i64
+define void @"0zNZN147MN2wzMAQ6NS2dQ==::f"() {
+0:
+	%1 = call i64 @"0zNZN147MN2wzMAQ6NS2dQ==::plus4"(i64 1)
+	ret void
+}
+define i64 @"0zNZN147MN2wzMAQ6NS2dQ==::plus4"(%"0zNZN147MN2wzMAQ6NS2dQ==::E" %e) {
+0:
+	%1 = alloca %"0zNZN147MN2wzMAQ6NS2dQ==::E"
+	store %"0zNZN147MN2wzMAQ6NS2dQ==::E" %e, ptr %1
+	%2 = load %"0zNZN147MN2wzMAQ6NS2dQ==::E", ptr %1
+	switch %"0zNZN147MN2wzMAQ6NS2dQ==::E" %2, label %8 [
+		%"0zNZN147MN2wzMAQ6NS2dQ==::E" 0, label %5
+		%"0zNZN147MN2wzMAQ6NS2dQ==::E" 1, label %6
+		%"0zNZN147MN2wzMAQ6NS2dQ==::E" 2, label %7
+	]
+3:
+	%4 = phi i64 [ 4, %5 ], [ 5, %6 ], [ 6, %7 ], [ -1, %8 ]
+	ret i64 %4
+5:
+	br label %3
+6:
+	br label %3
+7:
+	br label %3
+8:
+	br label %3
+}
+`,
+`
+E: Int
+| one
+| two
+| three
+
+[plus4 e:E]:Int = switch e
+	| E.one   4
+	| E.two   5
+	| E.three 6
+	*        -1
+[f] = [plus4 E.two]
+`)}
diff --git a/generator/expression-multiplex.go b/generator/expression-multiplex.go
index 4a4045e..14fbb00 100644
--- a/generator/expression-multiplex.go
+++ b/generator/expression-multiplex.go
@@ -101,6 +101,8 @@ func (this *generator) generateExpressionAny (expression entity.Expression) (reg
 		return this.generateLoop(expression, resultModeAny)
 	case *entity.For:
 		return this.generateFor(expression, resultModeAny)
+	case *entity.Constant:
+		return this.generateConstant(expression, resultModeAny)
 	
 	// we get nothing from these
 	case *entity.Assignment:
@@ -171,6 +173,9 @@ func (this *generator) generateExpressionVal (expression entity.Expression) (llv
 	case *entity.For:
 		val, _, err := this.generateFor(expression, resultModeVal)
 		return val, err
+	case *entity.Constant:
+		val, _, err := this.generateConstant(expression, resultModeVal)
+		return val, err
 	case *entity.LiteralInt:
 		return this.generateLiteralInt(expression)
 	case *entity.LiteralFloat:
@@ -249,6 +254,9 @@ func (this *generator) generateExpressionLoc (expression entity.Expression) (llv
 	case *entity.For:
 		loc, _, err := this.generateFor(expression, resultModeLoc)
 		return loc, err
+	case *entity.Constant:
+		loc, _, err := this.generateConstant(expression, resultModeLoc)
+		return loc, err
 	case *entity.LiteralArray:
 		return this.generateLiteralArrayLoc(expression, nil)
 	case *entity.LiteralString:
diff --git a/generator/expression.go b/generator/expression.go
index 3cd7fe7..0b08574 100644
--- a/generator/expression.go
+++ b/generator/expression.go
@@ -429,3 +429,10 @@ func (this *generator) generateFor (loop *entity.For, mode resultMode) (llvm.Val
 	}
 	return irValue, loopEntry.loc, nil
 }
+
+func (this *generator) generateConstant (constant *entity.Constant, mode resultMode) (llvm.Value, bool, error) {
+	// TODO for strings arrays and structs, make constant data in the
+	// module.
+	value := constant.Declaration.Value
+	return this.generateExpression(value, mode)
+}