clang/test/CodeGen/unsigned-shift-base.c

   1 // RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fsanitize=unsigned-shift-base,shift-exponent %s -emit-llvm -o - | FileCheck %s
   2
   3 // CHECK-LABEL: lsh_overflow(
   4 unsigned lsh_overflow(unsigned a, unsigned b) {
   5   // CHECK: %[[RHS_INBOUNDS:.*]] = icmp ule i32 %[[RHS:.*]], 31
   6   // CHECK-NEXT: br i1 %[[RHS_INBOUNDS]], label %[[CHECK_BB:.*]], label %[[CONT_BB:.*]],
   7
   8   // CHECK:      [[CHECK_BB]]:
   9   // CHECK-NEXT: %[[SHIFTED_OUT_WIDTH:.*]] = sub nuw nsw i32 31, %[[RHS]]
  10   // CHECK-NEXT: %[[SHIFTED_OUT:.*]] = lshr i32 %[[LHS:.*]], %[[SHIFTED_OUT_WIDTH]]
  11
  12   // CHECK-NEXT: %[[SHIFTED_OUT_NOT_SIGN:.*]] = lshr i32 %[[SHIFTED_OUT]], 1
  13
  14   // CHECK-NEXT: %[[NO_OVERFLOW:.*]] = icmp eq i32 %[[SHIFTED_OUT_NOT_SIGN]], 0
  15   // CHECK-NEXT: br label %[[CONT_BB]]
  16
  17   // CHECK:      [[CONT_BB]]:
  18   // CHECK-NEXT: %[[VALID_BASE:.*]] = phi i1 [ true, {{.*}} ], [ %[[NO_OVERFLOW]], %[[CHECK_BB]] ]
  19   // CHECK-NEXT: %[[VALID:.*]] = and i1 %[[RHS_INBOUNDS]], %[[VALID_BASE]]
  20   // CHECK-NEXT: br i1 %[[VALID]]
  21
  22   // CHECK: call void @__ubsan_handle_shift_out_of_bounds
  23   // CHECK-NOT: call void @__ubsan_handle_shift_out_of_bounds
  24
  25   // CHECK: %[[RET:.*]] = shl i32 %[[LHS]], %[[RHS]]
  26   // CHECK-NEXT: ret i32 %[[RET]]
  27   return a << b;
  28 }