codegen.c: peephole optimize OP_JMPxxx.

1 files changed, 32 insertions, 3 deletions

diff --git a/mrbgems/mruby-compiler/core/codegen.c b/mrbgems/mruby-compiler/core/codegen.c
index 70b95d7e3..8cc3bad7a 100644
--- a/mrbgems/mruby-compiler/core/codegen.c
+++ b/mrbgems/mruby-compiler/core/codegen.c
@@ -524,9 +524,38 @@ genjmp2(codegen_scope *s, mrb_code i, uint16_t a, uint32_t pc, int val)
   if (!no_peephole(s) && !val) {
     struct mrb_insn_data data = mrb_last_insn(s);
 
-    if (data.insn == OP_MOVE && data.a == a) {
-      rewind_pc(s);
-      a = data.b;
+    switch (data.insn) {
+    case OP_MOVE:
+      if (data.a == a && data.a > s->nlocals) {
+        rewind_pc(s);
+        a = data.b;
+      }
+      break;
+    case OP_LOADNIL:
+    case OP_LOADF:
+      if (data.a == a || data.a > s->nlocals) {
+        s->pc = addr_pc(s, data.addr);
+        if (i == OP_JMPNOT || (i == OP_JMPNIL && data.insn == OP_LOADNIL)) {
+          return genjmp(s, OP_JMP, pc);
+        }
+        else {                  /* OP_JMPIF */
+          return JMPLINK_START;
+        }
+      }
+      break;
+    case OP_LOADT: case OP_LOADI: case OP_LOADINEG: case OP_LOADI__1:
+    case OP_LOADI_0: case OP_LOADI_1: case OP_LOADI_2: case OP_LOADI_3:
+    case OP_LOADI_4: case OP_LOADI_5: case OP_LOADI_6: case OP_LOADI_7:
+      if (data.a == a || data.a > s->nlocals) {
+        s->pc = addr_pc(s, data.addr);
+        if (i == OP_JMPIF) {
+          return genjmp(s, OP_JMP, pc);
+        }
+        else {                  /* OP_JMPNOT and OP_JMPNIL */
+          return JMPLINK_START;
+        }
+      }
+      break;
     }
   }