private void atSwitchStmnt(Stmnt st) throws CompileError {
compileExpr(st.head());
ArrayList prevBreakList = breakList;
breakList = new ArrayList();
int opcodePc = bytecode.currentPc();
bytecode.addOpcode(LOOKUPSWITCH);
int npads = 3 - (opcodePc & 3);
while (npads-- > 0) bytecode.add(0);
Stmnt body = (Stmnt) st.tail();
int npairs = 0;
for (ASTList list = body; list != null; list = list.tail())
if (((Stmnt) list.head()).getOperator() == CASE) ++npairs;
// opcodePc2 is the position at which the default jump offset is.
int opcodePc2 = bytecode.currentPc();
bytecode.addGap(4);
bytecode.add32bit(npairs);
bytecode.addGap(npairs * 8);
long[] pairs = new long[npairs];
int ipairs = 0;
int defaultPc = -1;
for (ASTList list = body; list != null; list = list.tail()) {
Stmnt label = (Stmnt) list.head();
int op = label.getOperator();
if (op == DEFAULT) defaultPc = bytecode.currentPc();
else if (op != CASE) fatal();
else {
pairs[ipairs++] =
((long) computeLabel(label.head()) << 32)
+ ((long) (bytecode.currentPc() - opcodePc) & 0xffffffff);
}
hasReturned = false;
((Stmnt) label.tail()).accept(this);
}
Arrays.sort(pairs);
int pc = opcodePc2 + 8;
for (int i = 0; i < npairs; ++i) {
bytecode.write32bit(pc, (int) (pairs[i] >>> 32));
bytecode.write32bit(pc + 4, (int) pairs[i]);
pc += 8;
}
if (defaultPc < 0 || breakList.size() > 0) hasReturned = false;
int endPc = bytecode.currentPc();
if (defaultPc < 0) defaultPc = endPc;
bytecode.write32bit(opcodePc2, defaultPc - opcodePc);
patchGoto(breakList, endPc);
breakList = prevBreakList;
}
