/**
* Generate a boolean operation opcode
*
* <pre>
* 1) IF br != 0 THEN x=1 ELSE x=0 replaced by INT_MOVE x=br
* IF br == 0 THEN x=0 ELSE x=1
* 2) IF br == 0 THEN x=1 ELSE x=0 replaced by BOOLEAN_NOT x=br
* IF br != 0 THEN x=0 ELSE x=1
* 3) IF v1 ~ v2 THEN x=1 ELSE x=0 replaced by BOOLEAN_CMP x=v1,v2,~
* </pre>
*
* @param cb conditional branch instruction
* @param res the operand for result
* @param val1 value being compared
* @param val2 value being compared with
* @param cond comparison condition
*/
private void booleanCompareHelper(
Instruction cb, RegisterOperand res, Operand val1, Operand val2, ConditionOperand cond) {
if ((val1 instanceof RegisterOperand)
&& ((RegisterOperand) val1).getType().isBooleanType()
&& (val2 instanceof IntConstantOperand)) {
int value = ((IntConstantOperand) val2).value;
if (VM.VerifyAssertions && (value != 0) && (value != 1)) {
throw new OptimizingCompilerException("Invalid boolean value");
}
int c = cond.evaluate(value, 0);
if (c == ConditionOperand.TRUE) {
Unary.mutate(cb, BOOLEAN_NOT, res, val1);
return;
} else if (c == ConditionOperand.FALSE) {
Move.mutate(cb, INT_MOVE, res, val1);
return;
}
}
BooleanCmp.mutate(
cb,
(cb.operator() == REF_IFCMP) ? BOOLEAN_CMP_ADDR : BOOLEAN_CMP_INT,
res,
val1,
val2,
cond,
new BranchProfileOperand());
}
