llvm-project/clang/test/CodeGen/unsigned-promotion.c

// Check -fsanitize=signed-integer-overflow and
// -fsanitize=unsigned-integer-overflow with promoted unsigned types
//
// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm -o - %s \
// RUN:   -fsanitize=signed-integer-overflow | FileCheck %s --check-prefix=CHECKS
// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm -o - %s \
// RUN:   -fsanitize=unsigned-integer-overflow | FileCheck %s --check-prefix=CHECKU

unsigned short si, sj, sk;

// CHECKS-LABEL:   define void @testshortmul()
// CHECKU-LABEL: define void @testshortmul()
void testshortmul() {

  // CHECKS:        load i16, i16* @sj
  // CHECKS:        load i16, i16* @sk
  // CHECKS:        [[T1:%.*]] = call { i32, i1 } @llvm.smul.with.overflow.i32(i32 [[T2:%.*]], i32 [[T3:%.*]])
  // CHECKS-NEXT:   [[T4:%.*]] = extractvalue { i32, i1 } [[T1]], 0
  // CHECKS-NEXT:   [[T5:%.*]] = extractvalue { i32, i1 } [[T1]], 1
  // CHECKS:        call void @__ubsan_handle_mul_overflow
  //
  // CHECKU:      [[T1:%.*]] = load i16, i16* @sj
  // CHECKU:      [[T2:%.*]] = zext i16 [[T1]]
  // CHECKU:      [[T3:%.*]] = load i16, i16* @sk
  // CHECKU:      [[T4:%.*]] = zext i16 [[T3]]
  // CHECKU-NOT:  llvm.smul
  // CHECKU-NOT:  llvm.umul
  // CHECKU:      [[T5:%.*]] = mul nsw i32 [[T2]], [[T4]]
  si = sj * sk;
}