clang/test/CodeGen/assignment-tracking/memcpy-fragment.cpp

   1 // RUN: %clang_cc1 -triple x86_64-none-linux-gnu -debug-info-kind=standalone -O0 \
   2 // RUN:     -emit-llvm  -fexperimental-assignment-tracking=forced %s -o -        \
   3 // RUN:     -disable-O0-optnone                                                  \
   4 // RUN: | FileCheck %s
   5
   6 // Check that the (debug) codegen looks right with assignment tracking
   7 // enabled. Each fragment that is written to should have a dbg.assign that has
   8 // the DIAssignID of the write as an argument. The fragment offset and size
   9 // should match the offset into the base storage and size of the store. Each of
  10 // the scenarios below results in slightly different arguments generated for
  11 // the memcpy.
  12
  13 // Test write a complete struct field only.
  14 void fragmentWhole()
  15 {
  16  struct Record {
  17    int num;
  18    char ch;
  19  };
  20
  21  Record dest;
  22  char src = '\0';
  23  __builtin_memcpy(&dest.ch, &src, sizeof(char));
  24 }
  25 // CHECK: call void @llvm.memcpy{{.+}}, !DIAssignID ![[memberID:[0-9]+]]
  26 // CHECK-NEXT: call void @llvm.dbg.assign(metadata{{.*}}undef, metadata !{{[0-9]+}}, metadata !DIExpression(DW_OP_LLVM_fragment, 32, 8), metadata ![[memberID]], metadata ptr %ch, metadata !DIExpression())
  27
  28 // Write starting at a field and overlapping part of another.
  29 void fragmentWholeToPartial()
  30 {
  31  struct Record {
  32    int num1;
  33    int num2;
  34  };
  35
  36  Record dest;
  37  char src[5]="\0\0\0\0";
  38  __builtin_memcpy(&dest.num1, &src, 5);
  39 }
  40 // CHECK: call void @llvm.memcpy{{.+}}, !DIAssignID ![[exceed:[0-9]+]]
  41 // CHECK-NEXT: call void @llvm.dbg.assign(metadata{{.*}}undef, metadata !{{[0-9]+}}, metadata !DIExpression(DW_OP_LLVM_fragment, 0, 40), metadata ![[exceed]], metadata ptr %num1, metadata !DIExpression())
  42
  43 // Write starting between fields.
  44 void fragmentPartialToWhole()
  45 {
  46  struct record {
  47    int num1;
  48    int num2;
  49    int num3;
  50 };
  51
  52  record dest;
  53  char src[5]="\0\0\0\0";
  54  __builtin_memcpy((char*)&(dest.num2) + 3, &src, 5);
  55 }
  56 // CHECK: call void @llvm.memcpy{{.+}}, !DIAssignID ![[addendID:[0-9]+]]
  57 // CHECK-NEXT: call void @llvm.dbg.assign(metadata{{.*}}undef, metadata !{{.*}}, metadata !DIExpression(DW_OP_LLVM_fragment, 56, 40), metadata ![[addendID]], metadata ptr %add.ptr, metadata !DIExpression())