clang/test/CodeGen/abs-overflow.c

   1 // RUN: %clang_cc1 -triple x86_64 -emit-llvm %s -o - -fwrapv -fsanitize=signed-integer-overflow | FileCheck %s --check-prefix=WRAPV
   2 // RUN: %clang_cc1 -triple x86_64 -emit-llvm %s -o - -ftrapv | FileCheck %s --check-prefixes=BOTH-TRAP,TRAPV
   3 // RUN: %clang_cc1 -triple x86_64 -emit-llvm %s -o - -fsanitize=signed-integer-overflow | FileCheck %s --check-prefixes=BOTH-TRAP,CATCH_UB
   4 // COM: TODO: Support -ftrapv-handler.
   5
   6 extern int abs(int x);
   7
   8 int absi(int x) {
   9 // WRAPV:      [[ABS:%.*]] = call i32 @llvm.abs.i32(i32 %0, i1 false)
  10 // WRAPV-NEXT: ret i32 [[ABS]]
  11 //
  12 // BOTH-TRAP:       [[NEG:%.*]] = call { i32, i1 } @llvm.ssub.with.overflow.i32(i32 0, i32 [[X:%.*]])
  13 // BOTH-TRAP:       [[NEGV:%.*]] = extractvalue { i32, i1 } [[NEG]], 0
  14 // BOTH-TRAP:       [[OFL:%.*]] = extractvalue { i32, i1 } [[NEG]], 1
  15 // BOTH-TRAP:       [[NOFL:%.*]] = xor i1 [[OFL]], true
  16 // BOTH-TRAP:       br i1 [[NOFL]], label %[[CONT:.*]], label %[[TRAP:[a-zA-Z_.]*]]
  17 // BOTH-TRAP:       [[TRAP]]:
  18 // TRAPV-NEXT:        llvm.ubsantrap
  19 // CATCH_UB:          @__ubsan_handle_negate_overflow
  20 // BOTH-TRAP-NEXT:    unreachable
  21 // BOTH-TRAP:       [[CONT]]:
  22 // BOTH-TRAP-NEXT:    [[ABSCOND:%.*]] = icmp slt i32 [[X]], 0
  23 // BOTH-TRAP-NEXT:    select i1 [[ABSCOND]], i32 [[NEGV]], i32 [[X]]
  24   return abs(x);
  25 }
  26
  27 int babsi(int x) {
  28 // WRAPV:      [[ABS:%.*]] = call i32 @llvm.abs.i32(i32 %0, i1 false)
  29 // WRAPV-NEXT: ret i32 [[ABS]]
  30 //
  31 // BOTH-TRAP:       [[NEG:%.*]] = call { i32, i1 } @llvm.ssub.with.overflow.i32(i32 0, i32 [[X:%.*]])
  32 // BOTH-TRAP:       [[NEGV:%.*]] = extractvalue { i32, i1 } [[NEG]], 0
  33 // BOTH-TRAP:       [[OFL:%.*]] = extractvalue { i32, i1 } [[NEG]], 1
  34 // BOTH-TRAP:       [[NOFL:%.*]] = xor i1 [[OFL]], true
  35 // BOTH-TRAP:       br i1 [[NOFL]], label %[[CONT:.*]], label %[[TRAP:[a-zA-Z_.]*]]
  36 // BOTH-TRAP:       [[TRAP]]:
  37 // TRAPV-NEXT:        llvm.ubsantrap
  38 // CATCH_UB:          @__ubsan_handle_negate_overflow
  39 // BOTH-TRAP-NEXT:    unreachable
  40 // BOTH-TRAP:       [[CONT]]:
  41 // BOTH-TRAP-NEXT:    [[ABSCOND:%.*]] = icmp slt i32 [[X]], 0
  42 // BOTH-TRAP-NEXT:    select i1 [[ABSCOND]], i32 [[NEGV]], i32 [[X]]
  43   return __builtin_abs(x);
  44 }