return InsertValueInst::Create(Struct, II->getArgOperand(0), 0);
}
}
+
+ // We can strength reduce reduce this signed add into a regular add if we
+ // can prove that it will never overflow.
+ if (II->getIntrinsicID() == Intrinsic::sadd_with_overflow) {
+ Value *LHS = II->getArgOperand(0), *RHS = II->getArgOperand(1);
+ if (WillNotOverflowSignedAdd(LHS, RHS)) {
+ Value *Add = Builder->CreateNSWAdd(LHS, RHS);
+ Add->takeName(&CI);
+ Constant *V[] = {UndefValue::get(Add->getType()), Builder->getFalse()};
+ StructType *ST = cast<StructType>(II->getType());
+ Constant *Struct = ConstantStruct::get(ST, V);
+ return InsertValueInst::Create(Struct, Add, 0);
+ }
+ }
+
break;
case Intrinsic::usub_with_overflow:
case Intrinsic::ssub_with_overflow:
%overflow.result = type {i8, i1}
declare %overflow.result @llvm.uadd.with.overflow.i8(i8, i8)
+declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32)
declare %overflow.result @llvm.umul.with.overflow.i8(i8, i8)
declare double @llvm.powi.f64(double, i32) nounwind readonly
declare i32 @llvm.cttz.i32(i32, i1) nounwind readnone
; CHECK-NEXT: ret i8 %z
}
+; PR20194
+define { i32, i1 } @saddtest1(i8 %a, i8 %b) {
+ %A = sext i8 %a to i32
+ %B = sext i8 %b to i32
+ %x = call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %A, i32 %B)
+ ret { i32, i1 } %x
+; CHECK-LABEL: @saddtest1
+; CHECK: %x = add nsw i32 %A, %B
+; CHECK-NEXT: %1 = insertvalue { i32, i1 } { i32 undef, i1 false }, i32 %x, 0
+; CHECK-NEXT: ret { i32, i1 } %1
+}
+
define i8 @umultest1(i8 %A, i1* %overflowPtr) {
%x = call %overflow.result @llvm.umul.with.overflow.i8(i8 0, i8 %A)