// RUN: %clang_cc1 -fcatch-undefined-behavior -emit-llvm %s -o - -triple x86_64-linux-gnu | FileCheck %s // CHECK: @_Z17reference_binding void reference_binding(int *p) { // C++ core issue 453: If an lvalue to which a reference is directly bound // designates neither an existing object or function of an appropriate type, // nor a region of storage of suitable size and alignment to contain an object // of the reference's type, the behavior is undefined. // CHECK: icmp ne {{.*}}, null // CHECK: %[[SIZE:.*]] = call i64 @llvm.objectsize.i64 // CHECK-NEXT: icmp uge i64 %[[SIZE]], 4 // CHECK: %[[PTRINT:.*]] = ptrtoint // CHECK-NEXT: %[[MISALIGN:.*]] = and i64 %[[PTRINT]], 3 // CHECK-NEXT: icmp eq i64 %[[MISALIGN]], 0 int &r = *p; } struct S { double d; int a, b; virtual int f(); }; // CHECK: @_Z13member_access void member_access(S *p) { // (1) Check 'p' is appropriately sized and aligned for member access. // FIXME: Check vptr is for 'S' or a class derived from 'S'. // CHECK: icmp ne {{.*}}, null // CHECK: %[[SIZE:.*]] = call i64 @llvm.objectsize.i64 // CHECK-NEXT: icmp uge i64 %[[SIZE]], 24 // CHECK: %[[PTRINT:.*]] = ptrtoint // CHECK-NEXT: %[[MISALIGN:.*]] = and i64 %[[PTRINT]], 7 // CHECK-NEXT: icmp eq i64 %[[MISALIGN]], 0 // (2) Check 'p->b' is appropriately sized and aligned for a load. // FIXME: Suppress this in the trivial case of a member access, because we // know we've just checked the member access expression itself. // CHECK: %[[SIZE:.*]] = call i64 @llvm.objectsize.i64 // CHECK-NEXT: icmp uge i64 %[[SIZE]], 4 // CHECK: %[[PTRINT:.*]] = ptrtoint // CHECK-NEXT: %[[MISALIGN:.*]] = and i64 %[[PTRINT]], 3 // CHECK-NEXT: icmp eq i64 %[[MISALIGN]], 0 int k = p->b; // (3) Check 'p' is appropriately sized and aligned for member function call. // FIXME: Check vptr is for 'S' or a class derived from 'S'. // CHECK: icmp ne {{.*}}, null // CHECK: %[[SIZE:.*]] = call i64 @llvm.objectsize.i64 // CHECK-NEXT: icmp uge i64 %[[SIZE]], 24 // CHECK: %[[PTRINT:.*]] = ptrtoint // CHECK-NEXT: %[[MISALIGN:.*]] = and i64 %[[PTRINT]], 7 // CHECK-NEXT: icmp eq i64 %[[MISALIGN]], 0 k = p->f(); } // CHECK: @_Z12lsh_overflow int lsh_overflow(int a, int b) { // CHECK: %[[INBOUNDS:.*]] = icmp ule i32 %[[RHS:.*]], 31 // CHECK-NEXT: br i1 %[[INBOUNDS]] // CHECK: %[[SHIFTED_OUT_WIDTH:.*]] = sub nuw nsw i32 31, %[[RHS]] // CHECK-NEXT: %[[SHIFTED_OUT:.*]] = lshr i32 %[[LHS:.*]], %[[SHIFTED_OUT_WIDTH]] // This is present for C++11 but not for C: C++ core issue 1457 allows a '1' // to be shifted into the sign bit, but not out of it. // CHECK-NEXT: %[[SHIFTED_OUT_NOT_SIGN:.*]] = lshr i32 %[[SHIFTED_OUT]], 1 // CHECK-NEXT: %[[NO_OVERFLOW:.*]] = icmp eq i32 %[[SHIFTED_OUT_NOT_SIGN]], 0 // CHECK-NEXT: br i1 %[[NO_OVERFLOW]] // CHECK: %[[RET:.*]] = shl i32 %[[LHS]], %[[RHS]] // CHECK-NEXT: ret i32 %[[RET]] return a << b; }