Files
clang-p2996/lldb/test/Shell/Expr/TestExprWithSideEffectOnConvenienceVar.cpp
David Spickett 7d01b85c2a Reland "[lldb] Do not bump memory modificator ID when "internal" debugger memory is updated (#129092)"
This reverts commit daa4061d61.

Original PR https://github.com/llvm/llvm-project/pull/129092.

I have restricted the test to X86 Windows because it turns out the only
reason that `expr x.get()` would change m_memory_id is that on x86 we
have to write the return address to the stack in ABIWindows_X86_64::PrepareTrivialCall:
```
  // Save return address onto the stack
  if (!process_sp->WritePointerToMemory(sp, return_addr, error))
    return false;
```

This is not required on AArch64 so m_memory_id was not changed:
```
(lldb) expr x.get()
(int) $0 = 0
(lldb) process status -d
Process 15316 stopped
* thread #1, stop reason = Exception 0x80000003 encountered at address 0x7ff764a31034
    frame #0: 0x00007ff764a31038 TestProcessModificationIdOnExpr.cpp.tmp`main at TestProcessModificationIdOnExpr.cpp:35
   32     __builtin_debugtrap();
   33     __builtin_debugtrap();
   34     return 0;
-> 35   }
   36
   37   // CHECK-LABEL: process status -d
   38   // CHECK: m_stop_id: 2
ProcessModID:
  m_stop_id: 3
  m_last_natural_stop_id: 0
  m_resume_id: 0
  m_memory_id: 0
```

Really we should find a better way to force a memory write here, but
I can't think of one right now.
2025-05-02 13:00:12 +00:00

53 lines
1.2 KiB
C++

// Tests evaluating expressions with side effects on convenience variable.
// Applied side effect should be visible to the debugger.
// UNSUPPORTED: system-windows
// RUN: %build %s -o %t
// RUN: %lldb %t \
// RUN: -o "settings set target.process.track-memory-cache-changes false" \
// RUN: -o "run" \
// RUN: -o "expr int \$y = 11" \
// RUN: -o "expr \$y" \
// RUN: -o "expr \$y = 100" \
// RUN: -o "expr \$y" \
// RUN: -o "continue" \
// RUN: -o "expr \$y" \
// RUN: -o "expr X \$mine = {100, 200}" \
// RUN: -o "expr \$mine.a = 300" \
// RUN: -o "expr \$mine" \
// RUN: -o "exit" | FileCheck %s -dump-input=fail
struct X {
int a;
int b;
};
int main() {
X x;
__builtin_debugtrap();
__builtin_debugtrap();
return 0;
}
// CHECK-LABEL: expr int $y = 11
// CHECK-LABEL: expr $y
// CHECK: (int) $y = 11
// CHECK-LABEL: expr $y = 100
// CHECK: (int) $0 = 100
// CHECK-LABEL: expr $y
// CHECK: (int) $y = 100
// CHECK-LABEL: continue
// CHECK-LABEL: expr $y
// CHECK: (int) $y = 100
// CHECK-LABEL: expr X $mine = {100, 200}
// CHECK-LABEL: expr $mine.a = 300
// CHECK: (int) $1 = 300
// CHECK-LABEL: expr $mine
// CHECK: (X) $mine = (a = 300, b = 200)