ssa: add llvm debug info

ssa/decl.go

@@ -17,6 +17,7 @@
 package ssa
 
 import (
+	"go/token"
 	"go/types"
 	"log"
 	"strconv"
@@ -173,6 +174,8 @@ type aFunction struct {
 	freeVars Expr
 	base     int // base = 1 if hasFreeVars; base = 0 otherwise
 	hasVArg  bool
+
+	diFunc DIFunction
 }
 
 // Function represents a function or method.
@@ -274,6 +277,10 @@ func (p Function) NewBuilder() Builder {
 	return &aBuilder{b, nil, p, p.Pkg, prog}
 }
 
+func (p Function) NewDIBuilder() *llvm.DIBuilder {
+	return llvm.NewDIBuilder(p.Pkg.mod)
+}
+
 // HasBody reports whether the function has a body.
 func (p Function) HasBody() bool {
 	return len(p.blks) > 0
@@ -324,4 +331,33 @@ func (p Function) SetRecover(blk BasicBlock) {
 	p.recov = blk
 }
 
+func (p Function) scopeMeta(b diBuilder, pos token.Position) DIScopeMeta {
+	if p.diFunc == nil {
+		paramTypes := make([]llvm.Metadata, len(p.params))
+		for i, t := range p.params {
+			paramTypes[i] = b.DIType(t, pos).ll
+		}
+		diFuncType := b.di.CreateSubroutineType(llvm.DISubroutineType{
+			File:       b.DIFile(pos.Filename).ll,
+			Parameters: paramTypes,
+		})
+		p.diFunc = &aDIFunction{
+			b.di.CreateFunction(
+				p.Pkg.cu.ll,
+				llvm.DIFunction{
+					Type:         diFuncType,
+					Name:         p.Name(),
+					LinkageName:  p.Name(),
+					File:         b.DIFile(pos.Filename).ll,
+					Line:         pos.Line,
+					IsDefinition: true,
+					Optimized:    false,
+				},
+			),
+		}
+		p.impl.SetSubprogram(p.diFunc.ll)
+	}
+	return &aDIScopeMeta{p.diFunc.ll}
+}
+
 // -----------------------------------------------------------------------------