Introduce a native-only unwinder build.
Currently libunwind is built to support cross-unwinding [1] by default, which
requires the buffers unw_context_t and unw_cursor_t to be large enough to hold
the vritual register set (VRS) of any supported architecture. This is not
desirable for some platforms where the stack usage of the unwinder needs
to be kept to a minimum (e.g. bare-metal targets). The current patch introduces
a native-only (-DLIBUNWIND_ENABLE_CROSS_UNWINDING=OFF) unwinder variant that
adopts strict sizes for the buffers unw_context_t and unw_cursor_t depending
on the target architecture.
[1] http://www.nongnu.org/libunwind/man/libunwind(3).html#section_4
Change-Id: I380fff9a56c16a0fc520e3b1d8454a34b4a48373
llvm-svn: 270692
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 54387eef0772619db3aa2e08db3de5d690fe32c7
diff --git a/src/CompactUnwinder.hpp b/src/CompactUnwinder.hpp
index cd9ce3e..f528fba 100644
--- a/src/CompactUnwinder.hpp
+++ b/src/CompactUnwinder.hpp
@@ -27,6 +27,7 @@
namespace libunwind {
+#if defined(_LIBUNWIND_TARGET_I386)
/// CompactUnwinder_x86 uses a compact unwind info to virtually "step" (aka
/// unwind) by modifying a Registers_x86 register set
template <typename A>
@@ -255,8 +256,10 @@
// old esp is before return address
registers.setSP((uint32_t)returnAddressLocation + 4);
}
+#endif // _LIBUNWIND_TARGET_I386
+#if defined(_LIBUNWIND_TARGET_X86_64)
/// CompactUnwinder_x86_64 uses a compact unwind info to virtually "step" (aka
/// unwind) by modifying a Registers_x86_64 register set
template <typename A>
@@ -484,9 +487,11 @@
// old esp is before return address
registers.setSP(returnAddressLocation + 8);
}
+#endif // _LIBUNWIND_TARGET_X86_64
+#if defined(_LIBUNWIND_TARGET_AARCH64)
/// CompactUnwinder_arm64 uses a compact unwind info to virtually "step" (aka
/// unwind) by modifying a Registers_arm64 register set
template <typename A>
@@ -686,6 +691,7 @@
return UNW_STEP_SUCCESS;
}
+#endif // _LIBUNWIND_TARGET_AARCH64
} // namespace libunwind
diff --git a/src/Registers.hpp b/src/Registers.hpp
index 875ea20..51759bd 100644
--- a/src/Registers.hpp
+++ b/src/Registers.hpp
@@ -25,6 +25,7 @@
struct v128 { uint32_t vec[4]; };
+#if defined(_LIBUNWIND_TARGET_I386)
/// Registers_x86 holds the register state of a thread in a 32-bit intel
/// process.
class _LIBUNWIND_HIDDEN Registers_x86 {
@@ -86,8 +87,8 @@
};
inline Registers_x86::Registers_x86(const void *registers) {
- static_assert(sizeof(Registers_x86) < sizeof(unw_context_t),
- "x86 registers do not fit into unw_context_t");
+ static_assert(check_fit<Registers_x86, unw_context_t>::does_fit,
+ "x86 registers do not fit into unw_context_t");
memcpy(&_registers, registers, sizeof(_registers));
}
@@ -211,8 +212,10 @@
inline void Registers_x86::setVectorRegister(int, v128) {
_LIBUNWIND_ABORT("no x86 vector registers");
}
+#endif // _LIBUNWIND_TARGET_I386
+#if defined(_LIBUNWIND_TARGET_X86_64)
/// Registers_x86_64 holds the register state of a thread in a 64-bit intel
/// process.
class _LIBUNWIND_HIDDEN Registers_x86_64 {
@@ -278,8 +281,8 @@
};
inline Registers_x86_64::Registers_x86_64(const void *registers) {
- static_assert(sizeof(Registers_x86_64) < sizeof(unw_context_t),
- "x86_64 registers do not fit into unw_context_t");
+ static_assert(check_fit<Registers_x86_64, unw_context_t>::does_fit,
+ "x86_64 registers do not fit into unw_context_t");
memcpy(&_registers, registers, sizeof(_registers));
}
@@ -459,8 +462,10 @@
inline void Registers_x86_64::setVectorRegister(int, v128) {
_LIBUNWIND_ABORT("no x86_64 vector registers");
}
+#endif // _LIBUNWIND_TARGET_X86_64
+#if defined(_LIBUNWIND_TARGET_PPC)
/// Registers_ppc holds the register state of a thread in a 32-bit PowerPC
/// process.
class _LIBUNWIND_HIDDEN Registers_ppc {
@@ -543,8 +548,8 @@
};
inline Registers_ppc::Registers_ppc(const void *registers) {
- static_assert(sizeof(Registers_ppc) < sizeof(unw_context_t),
- "ppc registers do not fit into unw_context_t");
+ static_assert(check_fit<Registers_ppc, unw_context_t>::does_fit,
+ "ppc registers do not fit into unw_context_t");
memcpy(&_registers, static_cast<const uint8_t *>(registers),
sizeof(_registers));
static_assert(sizeof(ppc_thread_state_t) == 160,
@@ -1023,8 +1028,10 @@
}
}
+#endif // _LIBUNWIND_TARGET_PPC
+#if defined(_LIBUNWIND_TARGET_AARCH64)
/// Registers_arm64 holds the register state of a thread in a 64-bit arm
/// process.
class _LIBUNWIND_HIDDEN Registers_arm64 {
@@ -1071,8 +1078,8 @@
};
inline Registers_arm64::Registers_arm64(const void *registers) {
- static_assert(sizeof(Registers_arm64) < sizeof(unw_context_t),
- "arm64 registers do not fit into unw_context_t");
+ static_assert(check_fit<Registers_arm64, unw_context_t>::does_fit,
+ "arm64 registers do not fit into unw_context_t");
memcpy(&_registers, registers, sizeof(_registers));
static_assert(sizeof(GPRs) == 0x110,
"expected VFP registers to be at offset 272");
@@ -1289,7 +1296,9 @@
inline void Registers_arm64::setVectorRegister(int, v128) {
_LIBUNWIND_ABORT("no arm64 vector register support yet");
}
+#endif // _LIBUNWIND_TARGET_AARCH64
+#if defined(_LIBUNWIND_TARGET_ARM)
/// Registers_arm holds the register state of a thread in a 32-bit arm
/// process.
///
@@ -1395,8 +1404,8 @@
_saved_vfp_d16_d31(false),
_saved_iwmmx(false),
_saved_iwmmx_control(false) {
- static_assert(sizeof(Registers_arm) < sizeof(unw_context_t),
- "arm registers do not fit into unw_context_t");
+ static_assert(check_fit<Registers_arm, unw_context_t>::does_fit,
+ "arm registers do not fit into unw_context_t");
// See unw_getcontext() note about data.
memcpy(&_registers, registers, sizeof(_registers));
memset(&_vfp_d0_d15_pad, 0, sizeof(_vfp_d0_d15_pad));
@@ -1711,6 +1720,10 @@
inline void Registers_arm::setVectorRegister(int, v128) {
_LIBUNWIND_ABORT("ARM vector support not implemented");
}
+#endif // _LIBUNWIND_TARGET_ARM
+
+
+#if defined(_LIBUNWIND_TARGET_OR1K)
/// Registers_or1k holds the register state of a thread in an OpenRISC1000
/// process.
class _LIBUNWIND_HIDDEN Registers_or1k {
@@ -1745,8 +1758,8 @@
};
inline Registers_or1k::Registers_or1k(const void *registers) {
- static_assert(sizeof(Registers_or1k) < sizeof(unw_context_t),
- "or1k registers do not fit into unw_context_t");
+ static_assert(check_fit<Registers_or1k, unw_context_t>::does_fit,
+ "or1k registers do not fit into unw_context_t");
memcpy(&_registers, static_cast<const uint8_t *>(registers),
sizeof(_registers));
}
@@ -1893,6 +1906,7 @@
}
}
+#endif // _LIBUNWIND_TARGET_OR1K
} // namespace libunwind
#endif // __REGISTERS_HPP__
diff --git a/src/UnwindCursor.hpp b/src/UnwindCursor.hpp
index 9068316..661ef4a 100644
--- a/src/UnwindCursor.hpp
+++ b/src/UnwindCursor.hpp
@@ -481,30 +481,39 @@
return stepWithCompactEncoding(dummy);
}
+#if defined(_LIBUNWIND_TARGET_X86_64)
int stepWithCompactEncoding(Registers_x86_64 &) {
return CompactUnwinder_x86_64<A>::stepWithCompactEncoding(
_info.format, _info.start_ip, _addressSpace, _registers);
}
+#endif
+#if defined(_LIBUNWIND_TARGET_I386)
int stepWithCompactEncoding(Registers_x86 &) {
return CompactUnwinder_x86<A>::stepWithCompactEncoding(
_info.format, (uint32_t)_info.start_ip, _addressSpace, _registers);
}
+#endif
+#if defined(_LIBUNWIND_TARGET_PPC)
int stepWithCompactEncoding(Registers_ppc &) {
return UNW_EINVAL;
}
+#endif
+#if defined(_LIBUNWIND_TARGET_AARCH64)
int stepWithCompactEncoding(Registers_arm64 &) {
return CompactUnwinder_arm64<A>::stepWithCompactEncoding(
_info.format, _info.start_ip, _addressSpace, _registers);
}
+#endif
bool compactSaysUseDwarf(uint32_t *offset=NULL) const {
R dummy;
return compactSaysUseDwarf(dummy, offset);
}
+#if defined(_LIBUNWIND_TARGET_X86_64)
bool compactSaysUseDwarf(Registers_x86_64 &, uint32_t *offset) const {
if ((_info.format & UNWIND_X86_64_MODE_MASK) == UNWIND_X86_64_MODE_DWARF) {
if (offset)
@@ -513,7 +522,9 @@
}
return false;
}
+#endif
+#if defined(_LIBUNWIND_TARGET_I386)
bool compactSaysUseDwarf(Registers_x86 &, uint32_t *offset) const {
if ((_info.format & UNWIND_X86_MODE_MASK) == UNWIND_X86_MODE_DWARF) {
if (offset)
@@ -522,11 +533,15 @@
}
return false;
}
+#endif
+#if defined(_LIBUNWIND_TARGET_PPC)
bool compactSaysUseDwarf(Registers_ppc &, uint32_t *) const {
return true;
}
+#endif
+#if defined(_LIBUNWIND_TARGET_AARCH64)
bool compactSaysUseDwarf(Registers_arm64 &, uint32_t *offset) const {
if ((_info.format & UNWIND_ARM64_MODE_MASK) == UNWIND_ARM64_MODE_DWARF) {
if (offset)
@@ -535,6 +550,7 @@
}
return false;
}
+#endif
#endif // _LIBUNWIND_SUPPORT_COMPACT_UNWIND
#if _LIBUNWIND_SUPPORT_DWARF_UNWIND
@@ -543,25 +559,35 @@
return dwarfEncoding(dummy);
}
+#if defined(_LIBUNWIND_TARGET_X86_64)
compact_unwind_encoding_t dwarfEncoding(Registers_x86_64 &) const {
return UNWIND_X86_64_MODE_DWARF;
}
+#endif
+#if defined(_LIBUNWIND_TARGET_I386)
compact_unwind_encoding_t dwarfEncoding(Registers_x86 &) const {
return UNWIND_X86_MODE_DWARF;
}
+#endif
+#if defined(_LIBUNWIND_TARGET_PPC)
compact_unwind_encoding_t dwarfEncoding(Registers_ppc &) const {
return 0;
}
+#endif
+#if defined(_LIBUNWIND_TARGET_AARCH64)
compact_unwind_encoding_t dwarfEncoding(Registers_arm64 &) const {
return UNWIND_ARM64_MODE_DWARF;
}
+#endif
+#if defined (_LIBUNWIND_TARGET_OR1K)
compact_unwind_encoding_t dwarfEncoding(Registers_or1k &) const {
return 0;
}
+#endif
#endif // _LIBUNWIND_SUPPORT_DWARF_UNWIND
@@ -577,7 +603,7 @@
UnwindCursor<A, R>::UnwindCursor(unw_context_t *context, A &as)
: _addressSpace(as), _registers(context), _unwindInfoMissing(false),
_isSignalFrame(false) {
- static_assert(sizeof(UnwindCursor<A, R>) < sizeof(unw_cursor_t),
+ static_assert(check_fit<UnwindCursor<A, R>, unw_cursor_t>::does_fit,
"UnwindCursor<> does not fit in unw_cursor_t");
memset(&_info, 0, sizeof(_info));
}
diff --git a/src/config.h b/src/config.h
index 46bb08a..151030c 100644
--- a/src/config.h
+++ b/src/config.h
@@ -119,5 +119,25 @@
#define _LIBUNWIND_TRACING_UNWINDING logUnwinding()
#endif
+#ifdef __cplusplus
+// Used to fit UnwindCursor and Registers_xxx types against unw_context_t /
+// unw_cursor_t sized memory blocks.
+#if defined(_LIBUNWIND_IS_NATIVE_ONLY)
+# define COMP_OP ==
+#else
+# define COMP_OP <
+#endif
+template <typename _Type, typename _Mem>
+struct check_fit {
+ template <typename T>
+ struct blk_count {
+ static const uint32_t count =
+ (sizeof(T) + sizeof(uint64_t) - 1) / sizeof(uint64_t);
+ };
+ static const bool does_fit =
+ (blk_count<_Type>::count COMP_OP blk_count<_Mem>::count);
+};
+#undef COMP_OP
+#endif // __cplusplus
#endif // LIBUNWIND_CONFIG_H
diff --git a/src/libunwind.cpp b/src/libunwind.cpp
index f9f32f0..95f2dc0 100644
--- a/src/libunwind.cpp
+++ b/src/libunwind.cpp
@@ -45,30 +45,27 @@
_LIBUNWIND_TRACE_API("unw_init_local(cursor=%p, context=%p)\n",
static_cast<void *>(cursor),
static_cast<void *>(context));
- // Use "placement new" to allocate UnwindCursor in the cursor buffer.
#if defined(__i386__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_x86
#elif defined(__x86_64__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_x86_64>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_x86_64
#elif defined(__ppc__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_ppc>(
- context, LocalAddressSpace::sThisAddressSpace);
-#elif defined(__arm64__) || defined(__aarch64__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm64>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_ppc
+#elif defined(__aarch64__)
+# define REGISTER_KIND Registers_arm64
#elif _LIBUNWIND_ARM_EHABI
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_arm>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_arm
#elif defined(__or1k__)
- new ((void *)cursor) UnwindCursor<LocalAddressSpace, Registers_or1k>(
- context, LocalAddressSpace::sThisAddressSpace);
+# define REGISTER_KIND Registers_or1k
#elif defined(__mips__)
-#warning The MIPS architecture is not supported.
+# warning The MIPS architecture is not supported.
#else
-#error Architecture not supported
+# error Architecture not supported
#endif
+ // Use "placement new" to allocate UnwindCursor in the cursor buffer.
+ new ((void *)cursor) UnwindCursor<LocalAddressSpace, REGISTER_KIND>(
+ context, LocalAddressSpace::sThisAddressSpace);
+#undef REGISTER_KIND
AbstractUnwindCursor *co = (AbstractUnwindCursor *)cursor;
co->setInfoBasedOnIPRegister();