[all-commits] [llvm/llvm-project] df6879: [lldb] Fix ARM32 inferior calls

[Jan Kratochvil via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: df6879ec0227a8a5e5697e505201d0f4444f03a4
      https://github.com/llvm/llvm-project/commit/df6879ec0227a8a5e5697e505201d0f4444f03a4
  Author: Jan Kratochvil <jan.kratochvil at redhat.com>
  Date:   2019-12-21 (Sat, 21 Dec 2019)

  Changed paths:
    M lldb/source/Core/PluginManager.cpp
    M lldb/source/Expression/IRExecutionUnit.cpp
    M lldb/source/Expression/IRMemoryMap.cpp
    M lldb/source/Host/common/HostInfoBase.cpp
    M lldb/source/Plugins/ExpressionParser/Clang/IRForTarget.cpp
    M lldb/source/Plugins/Process/POSIX/CrashReason.cpp

  Log Message:
  -----------
  [lldb] Fix ARM32 inferior calls

  echo -e '#include <unistd.h>\nint main(void){\nsync();return 0;}'|./bin/clang -g -x c -;./bin/lldb -o 'file ./a.out' -o 'b main' -o r -o 'p (void)sync()'

Actual:

  error: Expression can't be run, because there is no JIT compiled function

Expected:

  <nothing, sync() has been executed>

This patch has been checked by:
  D71707: clang-tidy: new bugprone-pointer-cast-widening
  https://reviews.llvm.org/D71707

Casting from 32-bit `void *` to `uint64_t` requires an intermediate `uintptr_t` cast otherwise the pointer gets sign-extended:

  echo -e '#include <stdio.h>\n#include <stdint.h>\nint main(void){void *p=(void *)0x80000000;unsigned long long ull=(unsigned long long)p;unsigned long long ull2=(unsigned long
long)(uintptr_t)p;printf("p=%p ull=0x%llx ull2=0x%llx\\n",p,ull,ull2);return 0;}'|gcc -Wall -m32 -x c -;./a.out
  <stdin>: In function ‘main’:
  <stdin>:3:66: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
  p=0x80000000 ull=0xffffffff80000000 ull2=0x80000000

With debug output:
Actual:

  IRMemoryMap::WriteMemory (0xb6ff8640, 0xffffffffb6f82158, 0x112) went to [0xb6ff8640..0xb6ff86b3)
  Code can be run in the target.
  Found function, has local address 0xffffffffb6f84000 and remote address 0xffffffffffffffff
  Couldn't disassemble function : Couldn't find code range for function _Z12$__lldb_exprPv
  Sections:
  [0xb6f84000+0x3c]->0xb6ff9020 (alignment 4, section ID 0, name .text)
  ...
  HandleCommand, command did not succeed
  error: Expression can't be run, because there is no JIT compiled function

Expected:

  IRMemoryMap::WriteMemory (0xb6ff8640, 0xb6faa15c, 0x128) went to [0xb6ff8640..0xb6ff86c3)
  IRExecutionUnit::GetRemoteAddressForLocal() found 0xb6fac000 in [0xb6fac000..0xb6fac040], and returned 0xb6ff9020 from [0xb6ff9020..0xb6ff9060].
  Code can be run in the target.
  Found function, has local address 0xb6fac000 and remote address 0xb6ff9020
  Function's code range is [0xb6ff9020+0x40]
  ...
  Function data has contents:
  0xb6ff9020: 10 4c 2d e9 08 b0 8d e2 08 d0 4d e2 00 40 a0 e1
  ...
  Function disassembly:
  0xb6ff9020: 0xe92d4c10   push   {r4, r10, r11, lr}

Differential revision: https://reviews.llvm.org/D71498