ssa: Lookup

cl/_testrt/map/in.go

@@ -1,13 +1,10 @@
 package main
 
-/*
 import (
 	"github.com/goplus/llgo/internal/runtime/c"
 )
-*/
 
 func main() {
 	a := map[int]int{23: 100, 7: 29}
-	_ = a
-	// c.Printf(c.Str("Hello %d\n"), a[23])
+	c.Printf(c.Str("Hello %d\n"), a[23])
 }

cl/_testrt/map/out.ll

@@ -2,6 +2,7 @@
 source_filename = "main"
 
 @"main.init$guard" = global ptr null
+@0 = private unnamed_addr constant [10 x i8] c"Hello %d\0A\00", align 1
 
 define void @main.init() {
 _llgo_0:
@@ -21,9 +22,12 @@ _llgo_0:
   call void @"github.com/goplus/llgo/internal/runtime.init"()
   call void @main.init()
   %0 = call ptr @"github.com/goplus/llgo/internal/runtime.MakeSmallMap"()
+  %1 = call i32 (ptr, ...) @printf(ptr @0, <null operand!>)
   ret void
 }
 
 declare void @"github.com/goplus/llgo/internal/runtime.init"()
 
 declare ptr @"github.com/goplus/llgo/internal/runtime.MakeSmallMap"()
+
+declare i32 @printf(ptr, ...)

cl/compile.go

@@ -520,8 +520,12 @@ func (p *context) compileInstrOrValue(b llssa.Builder, iv instrOrValue, asValue
 					return p.compileValue(b, n.X)
 				}
 			}
-			panic(fmt.Errorf("todo addr of %v", e))
+			panic(fmt.Errorf("todo: addr of %v", e))
 		})
+	case *ssa.Lookup:
+		x := p.compileValue(b, v.X)
+		idx := p.compileValue(b, v.Index)
+		ret = b.Lookup(x, idx, v.CommaOk)
 	case *ssa.Slice:
 		vx := v.X
 		if _, ok := p.isVArgs(vx); ok { // varargs: this is a varargs slice

ssa/expr.go

@@ -654,6 +654,26 @@ func (b Builder) Index(x, idx Expr, addr func(Expr) Expr) Expr {
 	return b.Load(buf)
 }
 
+// The Lookup instruction yields element Index of collection map X.
+// Index is the appropriate key type.
+//
+// If CommaOk, the result is a 2-tuple of the value above and a
+// boolean indicating the result of a map membership test for the key.
+// The components of the tuple are accessed using Extract.
+//
+// Example printed form:
+//
+//	t2 = t0[t1]
+//	t5 = t3[t4],ok
+func (b Builder) Lookup(x, key Expr, commaOk bool) (ret Expr) {
+	if debugInstr {
+		log.Printf("Lookup %v, %v, %v\n", x.impl, key.impl, commaOk)
+	}
+	// TODO(xsw)
+	// panic("todo")
+	return
+}
+
 // The Slice instruction yields a slice of an existing string, slice
 // or *array X between optional integer bounds Low and High.
 //