Fix wrong update phi.

Change-Id: Ifa57e36bcf053aa4e4b10352f7bc558301eea786
diff --git a/src/compiler_llvm/gbc_expander.cc b/src/compiler_llvm/gbc_expander.cc
index fbd4a11..88505ee 100644
--- a/src/compiler_llvm/gbc_expander.cc
+++ b/src/compiler_llvm/gbc_expander.cc
@@ -420,6 +420,8 @@
 
   for (llvm::Function::iterator bb_iter = func_->begin();
        num_basic_blocks > 0; ++bb_iter, --num_basic_blocks) {
+    // Set insert point to current basic block.
+    irb_.SetInsertPoint(bb_iter);
 
     // Rewrite the basic block
     RewriteBasicBlock(bb_iter);