compiler: remove jumps to the next instruction

In case there are no returns in the inlined function, jumps point to the next instruction and can be omitted. This optimization can be extended to handle other cases, here we just make sure that already existing code stays the same. Signed-off-by: Evgeniy Stratonikov <[email protected]>
nspcc-dev · Jul 12, 2022 · 17329ee · 17329ee
1 parent 05efc57
commit 17329ee
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Showing 2 changed files with 7 additions and 4 deletions.
diff --git a/pkg/compiler/codegen.go b/pkg/compiler/codegen.go
@@ -2244,8 +2244,13 @@ func (c *codegen) writeJumps(b []byte) ([]byte, error) {
 				return nil, err
 			}
 			if op != opcode.PUSHA && math.MinInt8 <= offset && offset <= math.MaxInt8 {
-				copy(b[ctx.IP():], []byte{byte(toShortForm(op)), byte(offset), byte(opcode.NOP), byte(opcode.NOP), byte(opcode.NOP)})
-				nopOffsets = append(nopOffsets, ctx.IP()+2, ctx.IP()+3, ctx.IP()+4)
+				if op == opcode.JMPL && offset == 5 {
+					copy(b[ctx.IP():], []byte{byte(opcode.NOP), byte(opcode.NOP), byte(opcode.NOP), byte(opcode.NOP), byte(opcode.NOP)})
+					nopOffsets = append(nopOffsets, ctx.IP(), ctx.IP()+1, ctx.IP()+2, ctx.IP()+3, ctx.IP()+4)
+				} else {
+					copy(b[ctx.IP():], []byte{byte(toShortForm(op)), byte(offset), byte(opcode.NOP), byte(opcode.NOP), byte(opcode.NOP)})
+					nopOffsets = append(nopOffsets, ctx.IP()+2, ctx.IP()+3, ctx.IP()+4)
+				}
 			}
 		case opcode.INITSLOT:
 			nextIP := ctx.NextIP()

diff --git a/pkg/compiler/inline_test.go b/pkg/compiler/inline_test.go
@@ -281,7 +281,6 @@ func TestInlineVariadicInInlinedCall(t *testing.T) {
 }
 
 func TestInlineConversion(t *testing.T) {
-	t.Skip()
 	src1 := `package foo
 	import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/inline"
 	var _ = inline.A
@@ -307,7 +306,6 @@ func TestInlineConversion(t *testing.T) {
 }
 
 func TestInlineConversionQualified(t *testing.T) {
-	t.Skip()
 	src1 := `package foo
 	import "github.com/nspcc-dev/neo-go/pkg/compiler/testdata/inline"
 	var A = 1