Commit 6295415da72eb17b263494a070fdf957e89460fb | zig

author	Andrew Kelley <andrew@ziglang.org> 2024-04-26 14:40:08-07:00
committer	Andrew Kelley <andrew@ziglang.org> 2024-05-08 19:37:29-07:00
log	6295415da72eb17b263494a070fdf957e89460fb
tree	308c2c6341b137085dd9dc20168e2509572c2216
parent	a6856ef6d21635641320761a8f17205fd6e99fa9

libunwind: update to LLVM 18

release/18.x branch, commit 78b99c73ee4b96fe9ce0e294d4632326afb2db42

17 files changed, 389 insertions(+), 128 deletions(-)

lib
- libunwind
  - include
    __libunwind_config.h
    libunwind.h
    mach-o
    compact_unwind_encoding.h
  - src
    AddressSpace.hpp
    DwarfInstructions.hpp
    EHHeaderParser.hpp
    FrameHeaderCache.hpp
    Registers.hpp
    Unwind-sjlj.c
    Unwind-wasm.c
    UnwindCursor.hpp
    UnwindLevel1-gcc-ext.c
    UnwindRegistersRestore.S
    UnwindRegistersSave.S
    config.h
    libunwind.cpp
src
- libunwind.zig

lib/libunwind/include/__libunwind_config.h+4-1

...	...	@@ -36,6 +36,9 @@
36	36	# if defined(__linux__)
37	37	# define _LIBUNWIND_TARGET_LINUX 1
38	38	# endif
	39	# if defined(__HAIKU__)
	40	# define _LIBUNWIND_TARGET_HAIKU 1
	41	# endif
39	42	# if defined(__i386__)
40	43	# define _LIBUNWIND_TARGET_I386
41	44	# define _LIBUNWIND_CONTEXT_SIZE 8
...	...	@@ -196,7 +199,7 @@
196	199	# define _LIBUNWIND_TARGET_RISCV 1
197	200	# define _LIBUNWIND_TARGET_VE 1
198	201	# define _LIBUNWIND_TARGET_S390X 1
199		#define _LIBUNWIND_TARGET_LOONGARCH 1
	202	# define _LIBUNWIND_TARGET_LOONGARCH 1
200	203	# define _LIBUNWIND_CONTEXT_SIZE 167
201	204	# define _LIBUNWIND_CURSOR_SIZE 204
202	205	# define _LIBUNWIND_HIGHEST_DWARF_REGISTER 287

lib/libunwind/include/libunwind.h+3

...	...	@@ -876,6 +876,9 @@ enum {
876	876	UNW_MIPS_F29 = 61,
877	877	UNW_MIPS_F30 = 62,
878	878	UNW_MIPS_F31 = 63,
	879	// HI,LO have been dropped since r6, we keep them here.
	880	// So, when we add DSP/MSA etc, we can use the same register indexes
	881	// for r6 and pre-r6.
879	882	UNW_MIPS_HI = 64,
880	883	UNW_MIPS_LO = 65,
881	884	};

lib/libunwind/include/mach-o/compact_unwind_encoding.h+40-40

...	...	@@ -108,7 +108,7 @@ enum {
108	108	// are encoded in the UNWIND_X86_EBP_FRAME_REGISTERS bits as five 3-bit entries.
109	109	// Each entry contains which register to restore.
110	110	// UNWIND_X86_MODE_STACK_IMMD:
111		// A "frameless" (EBP not used as frame pointer) function with a small
	111	// A "frameless" (EBP not used as frame pointer) function with a small
112	112	// constant stack size. To return, a constant (encoded in the compact
113	113	// unwind encoding) is added to the ESP. Then the return is done by
114	114	// popping the stack into the pc.
...	...	@@ -119,16 +119,16 @@ enum {
119	119	// UNWIND_X86_FRAMELESS_STACK_REG_PERMUTATION contains which registers were
120	120	// saved and their order.
121	121	// UNWIND_X86_MODE_STACK_IND:
122		// A "frameless" (EBP not used as frame pointer) function large constant
	122	// A "frameless" (EBP not used as frame pointer) function large constant
123	123	// stack size. This case is like the previous, except the stack size is too
124		// large to encode in the compact unwind encoding. Instead it requires that
125		// the function contains "subl $nnnnnnnn,ESP" in its prolog. The compact
	124	// large to encode in the compact unwind encoding. Instead it requires that
	125	// the function contains "subl $nnnnnnnn,ESP" in its prolog. The compact
126	126	// encoding contains the offset to the nnnnnnnn value in the function in
127		// UNWIND_X86_FRAMELESS_STACK_SIZE.
	127	// UNWIND_X86_FRAMELESS_STACK_SIZE.
128	128	// UNWIND_X86_MODE_DWARF:
129	129	// No compact unwind encoding is available. Instead the low 24-bits of the
130	130	// compact encoding is the offset of the DWARF FDE in the __eh_frame section.
131		// This mode is never used in object files. It is only generated by the
	131	// This mode is never used in object files. It is only generated by the
132	132	// linker in final linked images which have only DWARF unwind info for a
133	133	// function.
134	134	//
...	...	@@ -233,36 +233,36 @@ enum {
233	233	// For x86_64 there are four modes for the compact unwind encoding:
234	234	// UNWIND_X86_64_MODE_RBP_FRAME:
235	235	// RBP based frame where RBP is push on stack immediately after return address,
236		// then RSP is moved to RBP. Thus, to unwind RSP is restored with the current
237		// EPB value, then RBP is restored by popping off the stack, and the return
	236	// then RSP is moved to RBP. Thus, to unwind RSP is restored with the current
	237	// EPB value, then RBP is restored by popping off the stack, and the return
238	238	// is done by popping the stack once more into the pc.
239	239	// All non-volatile registers that need to be restored must have been saved
240		// in a small range in the stack that starts RBP-8 to RBP-2040. The offset/8
	240	// in a small range in the stack that starts RBP-8 to RBP-2040. The offset/8
241	241	// is encoded in the UNWIND_X86_64_RBP_FRAME_OFFSET bits. The registers saved
242	242	// are encoded in the UNWIND_X86_64_RBP_FRAME_REGISTERS bits as five 3-bit entries.
243		// Each entry contains which register to restore.
	243	// Each entry contains which register to restore.
244	244	// UNWIND_X86_64_MODE_STACK_IMMD:
245		// A "frameless" (RBP not used as frame pointer) function with a small
246		// constant stack size. To return, a constant (encoded in the compact
247		// unwind encoding) is added to the RSP. Then the return is done by
	245	// A "frameless" (RBP not used as frame pointer) function with a small
	246	// constant stack size. To return, a constant (encoded in the compact
	247	// unwind encoding) is added to the RSP. Then the return is done by
248	248	// popping the stack into the pc.
249	249	// All non-volatile registers that need to be restored must have been saved
250	250	// on the stack immediately after the return address. The stack_size/8 is
251	251	// encoded in the UNWIND_X86_64_FRAMELESS_STACK_SIZE (max stack size is 2048).
252	252	// The number of registers saved is encoded in UNWIND_X86_64_FRAMELESS_STACK_REG_COUNT.
253	253	// UNWIND_X86_64_FRAMELESS_STACK_REG_PERMUTATION contains which registers were
254		// saved and their order.
	254	// saved and their order.
255	255	// UNWIND_X86_64_MODE_STACK_IND:
256		// A "frameless" (RBP not used as frame pointer) function large constant
	256	// A "frameless" (RBP not used as frame pointer) function large constant
257	257	// stack size. This case is like the previous, except the stack size is too
258		// large to encode in the compact unwind encoding. Instead it requires that
259		// the function contains "subq $nnnnnnnn,RSP" in its prolog. The compact
	258	// large to encode in the compact unwind encoding. Instead it requires that
	259	// the function contains "subq $nnnnnnnn,RSP" in its prolog. The compact
260	260	// encoding contains the offset to the nnnnnnnn value in the function in
261		// UNWIND_X86_64_FRAMELESS_STACK_SIZE.
	261	// UNWIND_X86_64_FRAMELESS_STACK_SIZE.
262	262	// UNWIND_X86_64_MODE_DWARF:
263	263	// No compact unwind encoding is available. Instead the low 24-bits of the
264	264	// compact encoding is the offset of the DWARF FDE in the __eh_frame section.
265		// This mode is never used in object files. It is only generated by the
	265	// This mode is never used in object files. It is only generated by the
266	266	// linker in final linked images which have only DWARF unwind info for a
267	267	// function.
268	268	//
...	...	@@ -307,20 +307,20 @@ enum {
307	307	// This is a standard arm64 prolog where FP/LR are immediately pushed on the
308	308	// stack, then SP is copied to FP. If there are any non-volatile registers
309	309	// saved, then are copied into the stack frame in pairs in a contiguous
310		// range right below the saved FP/LR pair. Any subset of the five X pairs
	310	// range right below the saved FP/LR pair. Any subset of the five X pairs
311	311	// and four D pairs can be saved, but the memory layout must be in register
312		// number order.
	312	// number order.
313	313	// UNWIND_ARM64_MODE_FRAMELESS:
314		// A "frameless" leaf function, where FP/LR are not saved. The return address
	314	// A "frameless" leaf function, where FP/LR are not saved. The return address
315	315	// remains in LR throughout the function. If any non-volatile registers
316	316	// are saved, they must be pushed onto the stack before any stack space is
317	317	// allocated for local variables. The stack sized (including any saved
318		// non-volatile registers) divided by 16 is encoded in the bits
	318	// non-volatile registers) divided by 16 is encoded in the bits
319	319	// UNWIND_ARM64_FRAMELESS_STACK_SIZE_MASK.
320	320	// UNWIND_ARM64_MODE_DWARF:
321	321	// No compact unwind encoding is available. Instead the low 24-bits of the
322	322	// compact encoding is the offset of the DWARF FDE in the __eh_frame section.
323		// This mode is never used in object files. It is only generated by the
	323	// This mode is never used in object files. It is only generated by the
324	324	// linker in final linked images which have only DWARF unwind info for a
325	325	// function.
326	326	//
...	...	@@ -337,19 +337,19 @@ enum {
337	337
338	338	//
339	339	// A compiler can generated compact unwind information for a function by adding
340		// a "row" to the __LD,__compact_unwind section. This section has the
341		// S_ATTR_DEBUG bit set, so the section will be ignored by older linkers.
342		// It is removed by the new linker, so never ends up in final executables.
343		// This section is a table, initially with one row per function (that needs
	340	// a "row" to the __LD,__compact_unwind section. This section has the
	341	// S_ATTR_DEBUG bit set, so the section will be ignored by older linkers.
	342	// It is removed by the new linker, so never ends up in final executables.
	343	// This section is a table, initially with one row per function (that needs
344	344	// unwind info). The table columns and some conceptual entries are:
345	345	//
346	346	// range-start pointer to start of function/range
347		// range-length
348		// compact-unwind-encoding 32-bit encoding
	347	// range-length
	348	// compact-unwind-encoding 32-bit encoding
349	349	// personality-function or zero if no personality function
350	350	// lsda or zero if no LSDA data
351	351	//
352		// The length and encoding fields are 32-bits. The other are all pointer sized.
	352	// The length and encoding fields are 32-bits. The other are all pointer sized.
353	353	//
354	354	// In x86_64 assembly, these entry would look like:
355	355	//
...	...	@@ -372,23 +372,23 @@ enum {
372	372	// .quad except_tab1
373	373	//
374	374	//
375		// Notes: There is no need for any labels in the the __compact_unwind section.
376		// The use of the .set directive is to force the evaluation of the
	375	// Notes: There is no need for any labels in the __compact_unwind section.
	376	// The use of the .set directive is to force the evaluation of the
377	377	// range-length at assembly time, instead of generating relocations.
378	378	//
379		// To support future compiler optimizations where which non-volatile registers
	379	// To support future compiler optimizations where which non-volatile registers
380	380	// are saved changes within a function (e.g. delay saving non-volatiles until
381	381	// necessary), there can by multiple lines in the __compact_unwind table for one
382		// function, each with a different (non-overlapping) range and each with
383		// different compact unwind encodings that correspond to the non-volatiles
	382	// function, each with a different (non-overlapping) range and each with
	383	// different compact unwind encodings that correspond to the non-volatiles
384	384	// saved at that range of the function.
385	385	//
386	386	// If a particular function is so wacky that there is no compact unwind way
387		// to encode it, then the compiler can emit traditional DWARF unwind info.
	387	// to encode it, then the compiler can emit traditional DWARF unwind info.
388	388	// The runtime will use which ever is available.
389	389	//
390		// Runtime support for compact unwind encodings are only available on 10.6
391		// and later. So, the compiler should not generate it when targeting pre-10.6.
	390	// Runtime support for compact unwind encodings are only available on 10.6
	391	// and later. So, the compiler should not generate it when targeting pre-10.6.
392	392
393	393
394	394
...	...	@@ -402,7 +402,7 @@ enum {
402	402	//
403	403	// The __TEXT,__unwind_info section is laid out for an efficient two level lookup.
404	404	// The header of the section contains a coarse index that maps function address
405		// to the page (4096 byte block) containing the unwind info for that function.
	405	// to the page (4096 byte block) containing the unwind info for that function.
406	406	//
407	407
408	408	#define UNWIND_SECTION_VERSION 1

lib/libunwind/src/AddressSpace.hpp+4-3

...	...	@@ -414,8 +414,8 @@ static bool checkForUnwindInfoSegment(const Elf_Phdr *phdr, size_t image_base,
414	414	cbdata->sects->dwarf_index_section = eh_frame_hdr_start;
415	415	cbdata->sects->dwarf_index_section_length = phdr->p_memsz;
416	416	if (EHHeaderParser<LocalAddressSpace>::decodeEHHdr(
417		*cbdata->addressSpace, eh_frame_hdr_start, phdr->p_memsz,
418		hdrInfo)) {
	417	*cbdata->addressSpace, eh_frame_hdr_start,
	418	eh_frame_hdr_start + phdr->p_memsz, hdrInfo)) {
419	419	// .eh_frame_hdr records the start of .eh_frame, but not its size.
420	420	// Rely on a zero terminator to find the end of the section.
421	421	cbdata->sects->dwarf_section = hdrInfo.eh_frame_ptr;
...	...	@@ -638,7 +638,8 @@ inline bool LocalAddressSpace::findUnwindSections(pint_t targetAddr,
638	638	info.dwarf_index_section_length = SIZE_MAX;
639	639	EHHeaderParser<LocalAddressSpace>::EHHeaderInfo hdrInfo;
640	640	if (!EHHeaderParser<LocalAddressSpace>::decodeEHHdr(
641		*this, info.dwarf_index_section, info.dwarf_index_section_length,
	641	*this, info.dwarf_index_section,
	642	info.dwarf_index_section + info.dwarf_index_section_length,
642	643	hdrInfo)) {
643	644	return false;
644	645	}

lib/libunwind/src/DwarfInstructions.hpp+1-1

...	...	@@ -68,7 +68,7 @@ private:
68	68	return (pint_t)((sint_t)registers.getRegister((int)prolog.cfaRegister) +
69	69	prolog.cfaRegisterOffset);
70	70	if (prolog.cfaExpression != 0)
71		return evaluateExpression((pint_t)prolog.cfaExpression, addressSpace,
	71	return evaluateExpression((pint_t)prolog.cfaExpression, addressSpace,
72	72	registers, 0);
73	73	assert(0 && "getCFA(): unknown location");
74	74	__builtin_unreachable();

lib/libunwind/src/EHHeaderParser.hpp+13

...	...	@@ -55,6 +55,19 @@ template <typename A>
55	55	bool EHHeaderParser<A>::decodeEHHdr(A &addressSpace, pint_t ehHdrStart,
56	56	pint_t ehHdrEnd, EHHeaderInfo &ehHdrInfo) {
57	57	pint_t p = ehHdrStart;
	58
	59	// Ensure that we don't read data beyond the end of .eh_frame_hdr
	60	if (ehHdrEnd - ehHdrStart < 4) {
	61	// Don't print a message for an empty .eh_frame_hdr (this can happen if
	62	// the linker script defines symbols for it even in the empty case).
	63	if (ehHdrEnd == ehHdrStart)
	64	return false;
	65	_LIBUNWIND_LOG("unsupported .eh_frame_hdr at %" PRIx64
	66	": need at least 4 bytes of data but only got %zd",
	67	static_cast<uint64_t>(ehHdrStart),
	68	static_cast<size_t>(ehHdrEnd - ehHdrStart));
	69	return false;
	70	}
58	71	uint8_t version = addressSpace.get8(p++);
59	72	if (version != 1) {
60	73	_LIBUNWIND_LOG("unsupported .eh_frame_hdr version: %" PRIu8 " at %" PRIx64,

lib/libunwind/src/FrameHeaderCache.hpp+3-3

...	...	@@ -31,8 +31,8 @@
31	31
32	32	class _LIBUNWIND_HIDDEN FrameHeaderCache {
33	33	struct CacheEntry {
34		uintptr_t LowPC() { return Info.dso_base; };
35		uintptr_t HighPC() { return Info.dso_base + Info.text_segment_length; };
	34	uintptr_t LowPC() { return Info.dso_base; }
	35	uintptr_t HighPC() { return Info.dso_base + Info.text_segment_length; }
36	36	UnwindInfoSections Info;
37	37	CacheEntry *Next;
38	38	};
...	...	@@ -41,7 +41,7 @@ class _LIBUNWIND_HIDDEN FrameHeaderCache {
41	41
42	42	// Can't depend on the C++ standard library in libunwind, so use an array to
43	43	// allocate the entries, and two linked lists for ordering unused and recently
44		// used entries. FIXME: Would the the extra memory for a doubly-linked list
	44	// used entries. FIXME: Would the extra memory for a doubly-linked list
45	45	// be better than the runtime cost of traversing a very short singly-linked
46	46	// list on a cache miss? The entries themselves are all small and consecutive,
47	47	// so unlikely to cause page faults when following the pointers. The memory

lib/libunwind/src/Registers.hpp+18-2

...	...	@@ -619,6 +619,8 @@ public:
619	619	void setIP(uint32_t value) { _registers.__srr0 = value; }
620	620	uint64_t getCR() const { return _registers.__cr; }
621	621	void setCR(uint32_t value) { _registers.__cr = value; }
	622	uint64_t getLR() const { return _registers.__lr; }
	623	void setLR(uint32_t value) { _registers.__lr = value; }
622	624
623	625	private:
624	626	struct ppc_thread_state_t {
...	...	@@ -1189,6 +1191,8 @@ public:
1189	1191	void setIP(uint64_t value) { _registers.__srr0 = value; }
1190	1192	uint64_t getCR() const { return _registers.__cr; }
1191	1193	void setCR(uint64_t value) { _registers.__cr = value; }
	1194	uint64_t getLR() const { return _registers.__lr; }
	1195	void setLR(uint64_t value) { _registers.__lr = value; }
1192	1196
1193	1197	private:
1194	1198	struct ppc64_thread_state_t {
...	...	@@ -2869,7 +2873,7 @@ inline bool Registers_mips_o32::validRegister(int regNum) const {
2869	2873	return false;
2870	2874	if (regNum <= UNW_MIPS_R31)
2871	2875	return true;
2872		#if __mips_isa_rev != 6
	2876	#if __mips_isa_rev < 6
2873	2877	if (regNum == UNW_MIPS_HI)
2874	2878	return true;
2875	2879	if (regNum == UNW_MIPS_LO)
...	...	@@ -2903,10 +2907,12 @@ inline uint32_t Registers_mips_o32::getRegister(int regNum) const {
2903	2907	return _registers.__pc;
2904	2908	case UNW_REG_SP:
2905	2909	return _registers.__r[29];
	2910	#if __mips_isa_rev < 6
2906	2911	case UNW_MIPS_HI:
2907	2912	return _registers.__hi;
2908	2913	case UNW_MIPS_LO:
2909	2914	return _registers.__lo;
	2915	#endif
2910	2916	}
2911	2917	_LIBUNWIND_ABORT("unsupported mips_o32 register");
2912	2918	}
...	...	@@ -2936,11 +2942,13 @@ inline void Registers_mips_o32::setRegister(int regNum, uint32_t value) {
2936	2942	case UNW_REG_SP:
2937	2943	_registers.__r[29] = value;
2938	2944	return;
	2945	#if __mips_isa_rev < 6
2939	2946	case UNW_MIPS_HI:
2940	2947	_registers.__hi = value;
2941	2948	return;
2942	2949	case UNW_MIPS_LO:
2943	2950	_registers.__lo = value;
	2951	#endif
2944	2952	return;
2945	2953	}
2946	2954	_LIBUNWIND_ABORT("unsupported mips_o32 register");
...	...	@@ -3120,10 +3128,12 @@ inline const char *Registers_mips_o32::getRegisterName(int regNum) {
3120	3128	return "$f30";
3121	3129	case UNW_MIPS_F31:
3122	3130	return "$f31";
	3131	#if __mips_isa_rev < 6
3123	3132	case UNW_MIPS_HI:
3124	3133	return "$hi";
3125	3134	case UNW_MIPS_LO:
3126	3135	return "$lo";
	3136	#endif
3127	3137	default:
3128	3138	return "unknown register";
3129	3139	}
...	...	@@ -3193,7 +3203,7 @@ inline bool Registers_mips_newabi::validRegister(int regNum) const {
3193	3203	return false;
3194	3204	if (regNum <= UNW_MIPS_R31)
3195	3205	return true;
3196		#if __mips_isa_rev != 6
	3206	#if __mips_isa_rev < 6
3197	3207	if (regNum == UNW_MIPS_HI)
3198	3208	return true;
3199	3209	if (regNum == UNW_MIPS_LO)
...	...	@@ -3212,10 +3222,12 @@ inline uint64_t Registers_mips_newabi::getRegister(int regNum) const {
3212	3222	return _registers.__pc;
3213	3223	case UNW_REG_SP:
3214	3224	return _registers.__r[29];
	3225	#if __mips_isa_rev < 6
3215	3226	case UNW_MIPS_HI:
3216	3227	return _registers.__hi;
3217	3228	case UNW_MIPS_LO:
3218	3229	return _registers.__lo;
	3230	#endif
3219	3231	}
3220	3232	_LIBUNWIND_ABORT("unsupported mips_newabi register");
3221	3233	}
...	...	@@ -3233,12 +3245,14 @@ inline void Registers_mips_newabi::setRegister(int regNum, uint64_t value) {
3233	3245	case UNW_REG_SP:
3234	3246	_registers.__r[29] = value;
3235	3247	return;
	3248	#if __mips_isa_rev < 6
3236	3249	case UNW_MIPS_HI:
3237	3250	_registers.__hi = value;
3238	3251	return;
3239	3252	case UNW_MIPS_LO:
3240	3253	_registers.__lo = value;
3241	3254	return;
	3255	#endif
3242	3256	}
3243	3257	_LIBUNWIND_ABORT("unsupported mips_newabi register");
3244	3258	}
...	...	@@ -3417,10 +3431,12 @@ inline const char *Registers_mips_newabi::getRegisterName(int regNum) {
3417	3431	return "$f30";
3418	3432	case UNW_MIPS_F31:
3419	3433	return "$f31";
	3434	#if __mips_isa_rev < 6
3420	3435	case UNW_MIPS_HI:
3421	3436	return "$hi";
3422	3437	case UNW_MIPS_LO:
3423	3438	return "$lo";
	3439	#endif
3424	3440	default:
3425	3441	return "unknown register";
3426	3442	}

lib/libunwind/src/Unwind-sjlj.c+6-5

...	...	@@ -82,7 +82,8 @@ struct _Unwind_FunctionContext {
82	82	static _LIBUNWIND_THREAD_LOCAL struct _Unwind_FunctionContext *stack = NULL;
83	83	#endif
84	84
85		static struct _Unwind_FunctionContext *__Unwind_SjLj_GetTopOfFunctionStack() {
	85	static struct _Unwind_FunctionContext *
	86	__Unwind_SjLj_GetTopOfFunctionStack(void) {
86	87	#if defined(__APPLE__)
87	88	return _pthread_getspecific_direct(__PTK_LIBC_DYLD_Unwind_SjLj_Key);
88	89	#else
...	...	@@ -426,7 +427,7 @@ _LIBUNWIND_EXPORT uintptr_t _Unwind_GetGR(struct _Unwind_Context *context,
426	427	/// Called by personality handler during phase 2 to alter register values.
427	428	_LIBUNWIND_EXPORT void _Unwind_SetGR(struct _Unwind_Context *context, int index,
428	429	uintptr_t new_value) {
429		_LIBUNWIND_TRACE_API("_Unwind_SetGR(context=%p, reg=%d, value=0x%" PRIuPTR
	430	_LIBUNWIND_TRACE_API("_Unwind_SetGR(context=%p, reg=%d, value=0x%" PRIxPTR
430	431	")",
431	432	(void *)context, index, new_value);
432	433	_Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
...	...	@@ -437,7 +438,7 @@ _LIBUNWIND_EXPORT void _Unwind_SetGR(struct _Unwind_Context *context, int index,
437	438	/// Called by personality handler during phase 2 to get instruction pointer.
438	439	_LIBUNWIND_EXPORT uintptr_t _Unwind_GetIP(struct _Unwind_Context *context) {
439	440	_Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
440		_LIBUNWIND_TRACE_API("_Unwind_GetIP(context=%p) => 0x%" PRIu32,
	441	_LIBUNWIND_TRACE_API("_Unwind_GetIP(context=%p) => 0x%" PRIxPTR,
441	442	(void *)context, ufc->resumeLocation + 1);
442	443	return ufc->resumeLocation + 1;
443	444	}
...	...	@@ -450,7 +451,7 @@ _LIBUNWIND_EXPORT uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context,
450	451	int *ipBefore) {
451	452	_Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
452	453	*ipBefore = 0;
453		_LIBUNWIND_TRACE_API("_Unwind_GetIPInfo(context=%p, %p) => 0x%" PRIu32,
	454	_LIBUNWIND_TRACE_API("_Unwind_GetIPInfo(context=%p, %p) => 0x%" PRIxPTR,
454	455	(void )context, (void )ipBefore,
455	456	ufc->resumeLocation + 1);
456	457	return ufc->resumeLocation + 1;
...	...	@@ -460,7 +461,7 @@ _LIBUNWIND_EXPORT uintptr_t _Unwind_GetIPInfo(struct _Unwind_Context *context,
460	461	/// Called by personality handler during phase 2 to alter instruction pointer.
461	462	_LIBUNWIND_EXPORT void _Unwind_SetIP(struct _Unwind_Context *context,
462	463	uintptr_t new_value) {
463		_LIBUNWIND_TRACE_API("_Unwind_SetIP(context=%p, value=0x%" PRIuPTR ")",
	464	_LIBUNWIND_TRACE_API("_Unwind_SetIP(context=%p, value=0x%" PRIxPTR ")",
464	465	(void *)context, new_value);
465	466	_Unwind_FunctionContext_t ufc = (_Unwind_FunctionContext_t) context;
466	467	ufc->resumeLocation = new_value - 1;

lib/libunwind/src/Unwind-wasm.c created+123

...	...	@@ -0,0 +1,123 @@
	1	//===----------------------------------------------------------------------===//
	2	//
	3	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	4	// See https://llvm.org/LICENSE.txt for license information.
	5	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	6	//
	7	//
	8	// Implements Wasm exception handling proposal
	9	// (https://github.com/WebAssembly/exception-handling) based C++ exceptions
	10	//
	11	//===----------------------------------------------------------------------===//
	12
	13	#include <stdbool.h>
	14
	15	#include "config.h"
	16
	17	#ifdef __USING_WASM_EXCEPTIONS__
	18
	19	#include "unwind.h"
	20	#include <threads.h>
	21
	22	_Unwind_Reason_Code __gxx_personality_wasm0(int version, _Unwind_Action actions,
	23	uint64_t exceptionClass,
	24	_Unwind_Exception *unwind_exception,
	25	_Unwind_Context *context);
	26
	27	struct _Unwind_LandingPadContext {
	28	// Input information to personality function
	29	uintptr_t lpad_index; // landing pad index
	30	uintptr_t lsda; // LSDA address
	31
	32	// Output information computed by personality function
	33	uintptr_t selector; // selector value
	34	};
	35
	36	// Communication channel between compiler-generated user code and personality
	37	// function
	38	thread_local struct _Unwind_LandingPadContext __wasm_lpad_context;
	39
	40	/// Calls to this function is in landing pads in compiler-generated user code.
	41	/// In other EH schemes, stack unwinding is done by libunwind library, which
	42	/// calls the personality function for each each frame it lands. On the other
	43	/// hand, WebAssembly stack unwinding process is performed by a VM, and the
	44	/// personality function cannot be called from there. So the compiler inserts
	45	/// a call to this function in landing pads in the user code, which in turn
	46	/// calls the personality function.
	47	_Unwind_Reason_Code _Unwind_CallPersonality(void *exception_ptr) {
	48	struct _Unwind_Exception *exception_object =
	49	(struct _Unwind_Exception *)exception_ptr;
	50	_LIBUNWIND_TRACE_API("_Unwind_CallPersonality(exception_object=%p)",
	51	(void *)exception_object);
	52
	53	// Reset the selector.
	54	__wasm_lpad_context.selector = 0;
	55
	56	// Call personality function. Wasm does not have two-phase unwinding, so we
	57	// only do the cleanup phase.
	58	return __gxx_personality_wasm0(
	59	1, _UA_SEARCH_PHASE, exception_object->exception_class, exception_object,
	60	(struct _Unwind_Context *)&__wasm_lpad_context);
	61	}
	62
	63	/// Called by __cxa_throw.
	64	_LIBUNWIND_EXPORT _Unwind_Reason_Code
	65	_Unwind_RaiseException(_Unwind_Exception *exception_object) {
	66	_LIBUNWIND_TRACE_API("_Unwind_RaiseException(exception_object=%p)",
	67	(void *)exception_object);
	68	// Use Wasm EH's 'throw' instruction.
	69	__builtin_wasm_throw(0, exception_object);
	70	}
	71
	72	/// Called by __cxa_end_catch.
	73	_LIBUNWIND_EXPORT void
	74	_Unwind_DeleteException(_Unwind_Exception *exception_object) {
	75	_LIBUNWIND_TRACE_API("_Unwind_DeleteException(ex_obj=%p)",
	76	(void *)(exception_object));
	77	if (exception_object->exception_cleanup != NULL)
	78	(*exception_object->exception_cleanup)(_URC_FOREIGN_EXCEPTION_CAUGHT,
	79	exception_object);
	80	}
	81
	82	/// Called by personality handler to alter register values.
	83	_LIBUNWIND_EXPORT void _Unwind_SetGR(struct _Unwind_Context *context, int index,
	84	uintptr_t value) {
	85	_LIBUNWIND_TRACE_API("_Unwind_SetGR(context=%p, index=%d, value=%lu)",
	86	(void *)context, index, value);
	87	// We only use this function to set __wasm_lpad_context.selector field, which
	88	// is index 1 in the personality function.
	89	if (index == 1)
	90	((struct _Unwind_LandingPadContext *)context)->selector = value;
	91	}
	92
	93	/// Called by personality handler to get instruction pointer.
	94	_LIBUNWIND_EXPORT uintptr_t _Unwind_GetIP(struct _Unwind_Context *context) {
	95	// The result will be used as an 1-based index after decrementing 1, so we
	96	// increment 2 here
	97	uintptr_t result =
	98	((struct _Unwind_LandingPadContext *)context)->lpad_index + 2;
	99	_LIBUNWIND_TRACE_API("_Unwind_GetIP(context=%p) => %lu", (void *)context,
	100	result);
	101	return result;
	102	}
	103
	104	/// Not used in Wasm.
	105	_LIBUNWIND_EXPORT void _Unwind_SetIP(struct _Unwind_Context *context,
	106	uintptr_t value) {}
	107
	108	/// Called by personality handler to get LSDA for current frame.
	109	_LIBUNWIND_EXPORT uintptr_t
	110	_Unwind_GetLanguageSpecificData(struct _Unwind_Context *context) {
	111	uintptr_t result = ((struct _Unwind_LandingPadContext *)context)->lsda;
	112	_LIBUNWIND_TRACE_API("_Unwind_GetLanguageSpecificData(context=%p) => 0x%lx",
	113	(void *)context, result);
	114	return result;
	115	}
	116
	117	/// Not used in Wasm.
	118	_LIBUNWIND_EXPORT uintptr_t
	119	_Unwind_GetRegionStart(struct _Unwind_Context *context) {
	120	return 0;
	121	}
	122
	123	#endif // defined(__USING_WASM_EXCEPTIONS__)

lib/libunwind/src/UnwindCursor.hpp+114-59

...	...	@@ -33,6 +33,8 @@
33	33	#if defined(_LIBUNWIND_TARGET_LINUX) && \
34	34	(defined(_LIBUNWIND_TARGET_AARCH64) \|\| defined(_LIBUNWIND_TARGET_RISCV) \|\| \
35	35	defined(_LIBUNWIND_TARGET_S390X))
	36	#include <errno.h>
	37	#include <signal.h>
36	38	#include <sys/syscall.h>
37	39	#include <sys/uio.h>
38	40	#include <unistd.h>
...	...	@@ -990,6 +992,7 @@ private:
990	992	R dummy;
991	993	return stepThroughSigReturn(dummy);
992	994	}
	995	bool isReadableAddr(const pint_t addr) const;
993	996	#if defined(_LIBUNWIND_TARGET_AARCH64)
994	997	bool setInfoForSigReturn(Registers_arm64 &);
995	998	int stepThroughSigReturn(Registers_arm64 &);
...	...	@@ -2301,27 +2304,39 @@ int UnwindCursor<A, R>::stepWithTBTable(pint_t pc, tbtable *TBTable,
2301	2304	if (!getFunctionName(functionBuf, sizeof(functionBuf), &offset)) {
2302	2305	functionName = ".anonymous.";
2303	2306	}
2304		_LIBUNWIND_TRACE_UNWINDING("%s: Look up traceback table of func=%s at %p",
2305		__func__, functionName,
2306		reinterpret_cast<void *>(TBTable));
	2307	_LIBUNWIND_TRACE_UNWINDING(
	2308	"%s: Look up traceback table of func=%s at %p, pc=%p, "
	2309	"SP=%p, saves_lr=%d, stores_bc=%d",
	2310	__func__, functionName, reinterpret_cast<void *>(TBTable),
	2311	reinterpret_cast<void *>(pc),
	2312	reinterpret_cast<void *>(registers.getSP()), TBTable->tb.saves_lr,
	2313	TBTable->tb.stores_bc);
2307	2314	}
2308	2315
2309	2316	#if defined(__powerpc64__)
2310		// Instruction to reload TOC register "l r2,40(r1)"
	2317	// Instruction to reload TOC register "ld r2,40(r1)"
2311	2318	const uint32_t loadTOCRegInst = 0xe8410028;
2312	2319	const int32_t unwPPCF0Index = UNW_PPC64_F0;
2313	2320	const int32_t unwPPCV0Index = UNW_PPC64_V0;
2314	2321	#else
2315		// Instruction to reload TOC register "l r2,20(r1)"
	2322	// Instruction to reload TOC register "lwz r2,20(r1)"
2316	2323	const uint32_t loadTOCRegInst = 0x80410014;
2317	2324	const int32_t unwPPCF0Index = UNW_PPC_F0;
2318	2325	const int32_t unwPPCV0Index = UNW_PPC_V0;
2319	2326	#endif
2320	2327
	2328	// lastStack points to the stack frame of the next routine up.
	2329	pint_t curStack = static_cast<pint_t>(registers.getSP());
	2330	pint_t lastStack = reinterpret_cast<pint_t >(curStack);
	2331
	2332	if (lastStack == 0)
	2333	return UNW_STEP_END;
	2334
2321	2335	R newRegisters = registers;
2322	2336
2323		// lastStack points to the stack frame of the next routine up.
2324		pint_t lastStack = (reinterpret_cast<pint_t >(registers.getSP()));
	2337	// If backchain is not stored, use the current stack frame.
	2338	if (!TBTable->tb.stores_bc)
	2339	lastStack = curStack;
2325	2340
2326	2341	// Return address is the address after call site instruction.
2327	2342	pint_t returnAddress;
...	...	@@ -2331,33 +2346,41 @@ int UnwindCursor<A, R>::stepWithTBTable(pint_t pc, tbtable *TBTable,
2331	2346	reinterpret_cast<void *>(lastStack));
2332	2347
2333	2348	sigcontext sigContext = reinterpret_cast<sigcontext >(
2334		reinterpret_cast<char *>(lastStack) + STKMIN);
	2349	reinterpret_cast<char *>(lastStack) + STKMINALIGN);
2335	2350	returnAddress = sigContext->sc_jmpbuf.jmp_context.iar;
2336	2351
2337		_LIBUNWIND_TRACE_UNWINDING("From sigContext=%p, returnAddress=%p\n",
2338		reinterpret_cast<void *>(sigContext),
2339		reinterpret_cast<void *>(returnAddress));
2340
	2352	bool useSTKMIN = false;
2341	2353	if (returnAddress < 0x10000000) {
2342		// Try again using STKMINALIGN
	2354	// Try again using STKMIN.
2343	2355	sigContext = reinterpret_cast<sigcontext *>(
2344		reinterpret_cast<char *>(lastStack) + STKMINALIGN);
	2356	reinterpret_cast<char *>(lastStack) + STKMIN);
2345	2357	returnAddress = sigContext->sc_jmpbuf.jmp_context.iar;
2346	2358	if (returnAddress < 0x10000000) {
2347		_LIBUNWIND_TRACE_UNWINDING("Bad returnAddress=%p\n",
2348		reinterpret_cast<void *>(returnAddress));
	2359	_LIBUNWIND_TRACE_UNWINDING("Bad returnAddress=%p from sigcontext=%p",
	2360	reinterpret_cast<void *>(returnAddress),
	2361	reinterpret_cast<void *>(sigContext));
2349	2362	return UNW_EBADFRAME;
2350		} else {
2351		_LIBUNWIND_TRACE_UNWINDING("Tried again using STKMINALIGN: "
2352		"sigContext=%p, returnAddress=%p. "
2353		"Seems to be a valid address\n",
2354		reinterpret_cast<void *>(sigContext),
2355		reinterpret_cast<void *>(returnAddress));
2356	2363	}
	2364	useSTKMIN = true;
2357	2365	}
	2366	_LIBUNWIND_TRACE_UNWINDING("Returning from a signal handler %s: "
	2367	"sigContext=%p, returnAddress=%p. "
	2368	"Seems to be a valid address",
	2369	useSTKMIN ? "STKMIN" : "STKMINALIGN",
	2370	reinterpret_cast<void *>(sigContext),
	2371	reinterpret_cast<void *>(returnAddress));
	2372
2358	2373	// Restore the condition register from sigcontext.
2359	2374	newRegisters.setCR(sigContext->sc_jmpbuf.jmp_context.cr);
2360	2375
	2376	// Save the LR in sigcontext for stepping up when the function that
	2377	// raised the signal is a leaf function. This LR has the return address
	2378	// to the caller of the leaf function.
	2379	newRegisters.setLR(sigContext->sc_jmpbuf.jmp_context.lr);
	2380	_LIBUNWIND_TRACE_UNWINDING(
	2381	"Save LR=%p from sigcontext",
	2382	reinterpret_cast<void *>(sigContext->sc_jmpbuf.jmp_context.lr));
	2383
2361	2384	// Restore GPRs from sigcontext.
2362	2385	for (int i = 0; i < 32; ++i)
2363	2386	newRegisters.setRegister(i, sigContext->sc_jmpbuf.jmp_context.gpr[i]);
...	...	@@ -2380,13 +2403,26 @@ int UnwindCursor<A, R>::stepWithTBTable(pint_t pc, tbtable *TBTable,
2380	2403	}
2381	2404	} else {
2382	2405	// Step up a normal frame.
2383		returnAddress = reinterpret_cast<pint_t *>(lastStack)[2];
2384	2406
2385		_LIBUNWIND_TRACE_UNWINDING("Extract info from lastStack=%p, "
2386		"returnAddress=%p\n",
2387		reinterpret_cast<void *>(lastStack),
2388		reinterpret_cast<void *>(returnAddress));
2389		_LIBUNWIND_TRACE_UNWINDING("fpr_regs=%d, gpr_regs=%d, saves_cr=%d\n",
	2407	if (!TBTable->tb.saves_lr && registers.getLR()) {
	2408	// This case should only occur if we were called from a signal handler
	2409	// and the signal occurred in a function that doesn't save the LR.
	2410	returnAddress = static_cast<pint_t>(registers.getLR());
	2411	_LIBUNWIND_TRACE_UNWINDING("Use saved LR=%p",
	2412	reinterpret_cast<void *>(returnAddress));
	2413	} else {
	2414	// Otherwise, use the LR value in the stack link area.
	2415	returnAddress = reinterpret_cast<pint_t *>(lastStack)[2];
	2416	}
	2417
	2418	// Reset LR in the current context.
	2419	newRegisters.setLR(NULL);
	2420
	2421	_LIBUNWIND_TRACE_UNWINDING(
	2422	"Extract info from lastStack=%p, returnAddress=%p",
	2423	reinterpret_cast<void *>(lastStack),
	2424	reinterpret_cast<void *>(returnAddress));
	2425	_LIBUNWIND_TRACE_UNWINDING("fpr_regs=%d, gpr_regs=%d, saves_cr=%d",
2390	2426	TBTable->tb.fpr_saved, TBTable->tb.gpr_saved,
2391	2427	TBTable->tb.saves_cr);
2392	2428
...	...	@@ -2450,7 +2486,7 @@ int UnwindCursor<A, R>::stepWithTBTable(pint_t pc, tbtable *TBTable,
2450	2486
2451	2487	struct vec_ext vec_ext = reinterpret_cast<struct vec_ext >(charPtr);
2452	2488
2453		_LIBUNWIND_TRACE_UNWINDING("vr_saved=%d\n", vec_ext->vr_saved);
	2489	_LIBUNWIND_TRACE_UNWINDING("vr_saved=%d", vec_ext->vr_saved);
2454	2490
2455	2491	// Restore vector register(s) if saved on the stack.
2456	2492	if (vec_ext->vr_saved) {
...	...	@@ -2480,11 +2516,11 @@ int UnwindCursor<A, R>::stepWithTBTable(pint_t pc, tbtable *TBTable,
2480	2516
2481	2517	// Do we need to set the TOC register?
2482	2518	_LIBUNWIND_TRACE_UNWINDING(
2483		"Current gpr2=%p\n",
	2519	"Current gpr2=%p",
2484	2520	reinterpret_cast<void *>(newRegisters.getRegister(2)));
2485	2521	if (firstInstruction == loadTOCRegInst) {
2486	2522	_LIBUNWIND_TRACE_UNWINDING(
2487		"Set gpr2=%p from frame\n",
	2523	"Set gpr2=%p from frame",
2488	2524	reinterpret_cast<void >(reinterpret_cast<pint_t >(lastStack)[5]));
2489	2525	newRegisters.setRegister(2, reinterpret_cast<pint_t *>(lastStack)[5]);
2490	2526	}
...	...	@@ -2516,7 +2552,6 @@ int UnwindCursor<A, R>::stepWithTBTable(pint_t pc, tbtable *TBTable,
2516	2552	} else {
2517	2553	isSignalFrame = false;
2518	2554	}
2519
2520	2555	return UNW_STEP_SUCCESS;
2521	2556	}
2522	2557	#endif // defined(_LIBUNWIND_SUPPORT_TBTAB_UNWIND)
...	...	@@ -2668,20 +2703,12 @@ bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_arm64 &) {
2668	2703	// [1] https://github.com/torvalds/linux/blob/master/arch/arm64/kernel/vdso/sigreturn.S
2669	2704	const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP));
2670	2705	// The PC might contain an invalid address if the unwind info is bad, so
2671		// directly accessing it could cause a segfault. Use process_vm_readv to read
2672		// the memory safely instead. process_vm_readv was added in Linux 3.2, and
2673		// AArch64 supported was added in Linux 3.7, so the syscall is guaranteed to
2674		// be present. Unfortunately, there are Linux AArch64 environments where the
2675		// libc wrapper for the syscall might not be present (e.g. Android 5), so call
2676		// the syscall directly instead.
2677		uint32_t instructions[2];
2678		struct iovec local_iov = {&instructions, sizeof instructions};
2679		struct iovec remote_iov = {reinterpret_cast<void *>(pc), sizeof instructions};
2680		long bytesRead =
2681		syscall(SYS_process_vm_readv, getpid(), &local_iov, 1, &remote_iov, 1, 0);
	2706	// directly accessing it could cause a SIGSEGV.
	2707	if (!isReadableAddr(pc))
	2708	return false;
	2709	auto instructions = reinterpret_cast<const uint32_t >(pc);
2682	2710	// Look for instructions: mov x8, #0x8b; svc #0x0
2683		if (bytesRead != sizeof instructions \|\| instructions[0] != 0xd2801168 \|\|
2684		instructions[1] != 0xd4000001)
	2711	if (instructions[0] != 0xd2801168 \|\| instructions[1] != 0xd4000001)
2685	2712	return false;
2686	2713
2687	2714	_info = {};
...	...	@@ -2730,18 +2757,17 @@ int UnwindCursor<A, R>::stepThroughSigReturn(Registers_arm64 &) {
2730	2757	template <typename A, typename R>
2731	2758	bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_riscv &) {
2732	2759	const pint_t pc = static_cast<pint_t>(getReg(UNW_REG_IP));
2733		uint32_t instructions[2];
2734		struct iovec local_iov = {&instructions, sizeof instructions};
2735		struct iovec remote_iov = {reinterpret_cast<void *>(pc), sizeof instructions};
2736		long bytesRead =
2737		syscall(SYS_process_vm_readv, getpid(), &local_iov, 1, &remote_iov, 1, 0);
	2760	// The PC might contain an invalid address if the unwind info is bad, so
	2761	// directly accessing it could cause a SIGSEGV.
	2762	if (!isReadableAddr(pc))
	2763	return false;
	2764	const auto instructions = reinterpret_cast<const uint32_t >(pc);
2738	2765	// Look for the two instructions used in the sigreturn trampoline
2739	2766	// __vdso_rt_sigreturn:
2740	2767	//
2741	2768	// 0x08b00893 li a7,0x8b
2742	2769	// 0x00000073 ecall
2743		if (bytesRead != sizeof instructions \|\| instructions[0] != 0x08b00893 \|\|
2744		instructions[1] != 0x00000073)
	2770	if (instructions[0] != 0x08b00893 \|\| instructions[1] != 0x00000073)
2745	2771	return false;
2746	2772
2747	2773	_info = {};
...	...	@@ -2790,13 +2816,11 @@ bool UnwindCursor<A, R>::setInfoForSigReturn(Registers_s390x &) {
2790	2816	// onto the stack.
2791	2817	const pint_t pc = static_cast<pint_t>(this->getReg(UNW_REG_IP));
2792	2818	// The PC might contain an invalid address if the unwind info is bad, so
2793		// directly accessing it could cause a segfault. Use process_vm_readv to
2794		// read the memory safely instead.
2795		uint16_t inst;
2796		struct iovec local_iov = {&inst, sizeof inst};
2797		struct iovec remote_iov = {reinterpret_cast<void *>(pc), sizeof inst};
2798		long bytesRead = process_vm_readv(getpid(), &local_iov, 1, &remote_iov, 1, 0);
2799		if (bytesRead == sizeof inst && (inst == 0x0a77 \|\| inst == 0x0aad)) {
	2819	// directly accessing it could cause a SIGSEGV.
	2820	if (!isReadableAddr(pc))
	2821	return false;
	2822	const auto inst = reinterpret_cast<const uint16_t >(pc);
	2823	if (inst == 0x0a77 \|\| inst == 0x0aad) {
2800	2824	_info = {};
2801	2825	_info.start_ip = pc;
2802	2826	_info.end_ip = pc + 2;
...	...	@@ -2942,6 +2966,37 @@ bool UnwindCursor<A, R>::getFunctionName(char *buf, size_t bufLen,
2942	2966	buf, bufLen, offset);
2943	2967	}
2944	2968
	2969	#if defined(_LIBUNWIND_CHECK_LINUX_SIGRETURN)
	2970	template <typename A, typename R>
	2971	bool UnwindCursor<A, R>::isReadableAddr(const pint_t addr) const {
	2972	// We use SYS_rt_sigprocmask, inspired by Abseil's AddressIsReadable.
	2973
	2974	const auto sigsetAddr = reinterpret_cast<sigset_t *>(addr);
	2975	// We have to check that addr is nullptr because sigprocmask allows that
	2976	// as an argument without failure.
	2977	if (!sigsetAddr)
	2978	return false;
	2979	const auto saveErrno = errno;
	2980	// We MUST use a raw syscall here, as wrappers may try to access
	2981	// sigsetAddr which may cause a SIGSEGV. A raw syscall however is
	2982	// safe. Additionally, we need to pass the kernel_sigset_size, which is
	2983	// different from libc sizeof(sigset_t). For the majority of architectures,
	2984	// it's 64 bits (_NSIG), and libc NSIG is _NSIG + 1.
	2985	const auto kernelSigsetSize = NSIG / 8;
	2986	[[maybe_unused]] const int Result = syscall(
	2987	SYS_rt_sigprocmask, /how=/~0, sigsetAddr, nullptr, kernelSigsetSize);
	2988	// Because our "how" is invalid, this syscall should always fail, and our
	2989	// errno should always be EINVAL or an EFAULT. This relies on the Linux
	2990	// kernel to check copy_from_user before checking if the "how" argument is
	2991	// invalid.
	2992	assert(Result == -1);
	2993	assert(errno == EFAULT \|\| errno == EINVAL);
	2994	const auto readable = errno != EFAULT;
	2995	errno = saveErrno;
	2996	return readable;
	2997	}
	2998	#endif
	2999
2945	3000	#if defined(_LIBUNWIND_USE_CET)
2946	3001	extern "C" void __libunwind_cet_get_registers(unw_cursor_t cursor) {
2947	3002	AbstractUnwindCursor co = (AbstractUnwindCursor )cursor;

lib/libunwind/src/UnwindLevel1-gcc-ext.c+1-1

...	...	@@ -143,7 +143,7 @@ _Unwind_Backtrace(_Unwind_Trace_Fn callback, void *ref) {
143	143	// Create a mock exception object for force unwinding.
144	144	_Unwind_Exception ex;
145	145	memset(&ex, '\0', sizeof(ex));
146		strcpy((char *)&ex.exception_class, "CLNGUNW");
	146	memcpy(&ex.exception_class, "CLNGUNW", sizeof(ex.exception_class));
147	147	#endif
148	148
149	149	// walk each frame

lib/libunwind/src/UnwindRegistersRestore.S+5-1

...	...	@@ -673,7 +673,7 @@ DEFINE_LIBUNWIND_FUNCTION(__libunwind_Registers_arm64_jumpto)
673	673	ldr d30, [x0, #0x200]
674	674	ldr d31, [x0, #0x208]
675	675
676		// Finally, restore sp. This must be done after the the last read from the
	676	// Finally, restore sp. This must be done after the last read from the
677	677	// context struct, because it is allocated on the stack, and an exception
678	678	// could clobber the de-allocated portion of the stack after sp has been
679	679	// restored.
...	...	@@ -993,11 +993,13 @@ DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind18Registers_mips_o326jumptoEv)
993	993	ldc1 $f31, (4 * 36 + 8 * 31)($4)
994	994	#endif
995	995	#endif
	996	#if __mips_isa_rev < 6
996	997	// restore hi and lo
997	998	lw $8, (4 * 33)($4)
998	999	mthi $8
999	1000	lw $8, (4 * 34)($4)
1000	1001	mtlo $8
	1002	#endif
1001	1003	// r0 is zero
1002	1004	lw $1, (4 * 1)($4)
1003	1005	lw $2, (4 * 2)($4)
...	...	@@ -1054,11 +1056,13 @@ DEFINE_LIBUNWIND_FUNCTION(_ZN9libunwind21Registers_mips_newabi6jumptoEv)
1054	1056	ldc1 $f\i, (280+8*\i)($4)
1055	1057	.endr
1056	1058	#endif
	1059	#if __mips_isa_rev < 6
1057	1060	// restore hi and lo
1058	1061	ld $8, (8 * 33)($4)
1059	1062	mthi $8
1060	1063	ld $8, (8 * 34)($4)
1061	1064	mtlo $8
	1065	#endif
1062	1066	// r0 is zero
1063	1067	ld $1, (8 * 1)($4)
1064	1068	ld $2, (8 * 2)($4)

lib/libunwind/src/UnwindRegistersSave.S+41-3

...	...	@@ -174,11 +174,13 @@ DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
174	174	sw $31, (4 * 31)($4)
175	175	# Store return address to pc
176	176	sw $31, (4 * 32)($4)
	177	#if __mips_isa_rev < 6
177	178	# hi and lo
178	179	mfhi $8
179	180	sw $8, (4 * 33)($4)
180	181	mflo $8
181	182	sw $8, (4 * 34)($4)
	183	#endif
182	184	#ifdef __mips_hard_float
183	185	#if __mips_fpr != 64
184	186	sdc1 $f0, (4 * 36 + 8 * 0)($4)
...	...	@@ -255,11 +257,13 @@ DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
255	257	.endr
256	258	# Store return address to pc
257	259	sd $31, (8 * 32)($4)
	260	#if __mips_isa_rev < 6
258	261	# hi and lo
259	262	mfhi $8
260	263	sd $8, (8 * 33)($4)
261	264	mflo $8
262	265	sd $8, (8 * 34)($4)
	266	#endif
263	267	#ifdef __mips_hard_float
264	268	.irp i,FROM_0_TO_31
265	269	sdc1 $f\i, (280+8*\i)($4)
...	...	@@ -301,9 +305,21 @@ DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
301	305	mflr 0
302	306	std 0, PPC64_OFFS_SRR0(3) // store lr as ssr0
303	307	PPC64_STR(1)
	308	PPC64_STR(4) // Save r4 first since it will be used for fixing r2.
	309	#if defined(_AIX)
	310	// The TOC register (r2) was changed by the glue code if unw_getcontext
	311	// is called from a different module. Save the original TOC register
	312	// in the context if this is the case.
	313	mflr 4
	314	lwz 4, 0(4) // Get the first instruction at the return address.
	315	xoris 0, 4, 0xe841 // Is it reloading the TOC register "ld 2,40(1)"?
	316	cmplwi 0, 0x28
	317	bne 0, LnoR2Fix // No need to fix up r2 if it is not.
	318	ld 2, 40(1) // Use the saved TOC register in the stack.
	319	LnoR2Fix:
	320	#endif
304	321	PPC64_STR(2)
305	322	PPC64_STR(3)
306		PPC64_STR(4)
307	323	PPC64_STR(5)
308	324	PPC64_STR(6)
309	325	PPC64_STR(7)
...	...	@@ -336,7 +352,12 @@ DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
336	352	std 0, PPC64_OFFS_CR(3)
337	353	mfxer 0
338	354	std 0, PPC64_OFFS_XER(3)
	355	#if defined(_AIX)
	356	// LR value saved from the register is not used, initialize it to 0.
	357	li 0, 0
	358	#else
339	359	mflr 0
	360	#endif
340	361	std 0, PPC64_OFFS_LR(3)
341	362	mfctr 0
342	363	std 0, PPC64_OFFS_CTR(3)
...	...	@@ -543,9 +564,21 @@ DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
543	564	mflr 0
544	565	stw 0, 0(3) // store lr as ssr0
545	566	stw 1, 12(3)
	567	stw 4, 24(3) // Save r4 first since it will be used for fixing r2.
	568	#if defined(_AIX)
	569	// The TOC register (r2) was changed by the glue code if unw_getcontext
	570	// is called from a different module. Save the original TOC register
	571	// in the context if this is the case.
	572	mflr 4
	573	lwz 4, 0(4) // Get the instruction at the return address.
	574	xoris 0, 4, 0x8041 // Is it reloading the TOC register "lwz 2,20(1)"?
	575	cmplwi 0, 0x14
	576	bne 0, LnoR2Fix // No need to fix up r2 if it is not.
	577	lwz 2, 20(1) // Use the saved TOC register in the stack.
	578	LnoR2Fix:
	579	#endif
546	580	stw 2, 16(3)
547	581	stw 3, 20(3)
548		stw 4, 24(3)
549	582	stw 5, 28(3)
550	583	stw 6, 32(3)
551	584	stw 7, 36(3)
...	...	@@ -582,6 +615,11 @@ DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
582	615	// save CR registers
583	616	mfcr 0
584	617	stw 0, 136(3)
	618	#if defined(_AIX)
	619	// LR value from the register is not used, initialize it to 0.
	620	li 0, 0
	621	stw 0, 144(3)
	622	#endif
585	623	// save CTR register
586	624	mfctr 0
587	625	stw 0, 148(3)
...	...	@@ -742,7 +780,7 @@ DEFINE_LIBUNWIND_FUNCTION(__unw_getcontext)
742	780	@
743	781	@ On entry:
744	782	@ thread_state pointer is in r0
745		@
	783	@
746	784	@ Per EHABI #4.7 this only saves the core integer registers.
747	785	@ EHABI #7.4.5 notes that in general all VRS registers should be restored
748	786	@ however this is very hard to do for VFP registers because it is unknown

lib/libunwind/src/config.h+8-6

...	...	@@ -46,6 +46,12 @@
46	46	#elif defined(_AIX)
47	47	// The traceback table at the end of each function is used for unwinding.
48	48	#define _LIBUNWIND_SUPPORT_TBTAB_UNWIND 1
	49	#elif defined(__HAIKU__)
	50	#if defined(_LIBUNWIND_USE_HAIKU_BSD_LIB)
	51	#define _LIBUNWIND_USE_DL_ITERATE_PHDR 1
	52	#endif
	53	#define _LIBUNWIND_SUPPORT_DWARF_UNWIND 1
	54	#define _LIBUNWIND_SUPPORT_DWARF_INDEX 1
49	55	#else
50	56	// Assume an ELF system with a dl_iterate_phdr function.
51	57	#define _LIBUNWIND_USE_DL_ITERATE_PHDR 1
...	...	@@ -83,7 +89,7 @@
83	89	__asm__(".globl " SYMBOL_NAME(aliasname)); \
84	90	__asm__(SYMBOL_NAME(aliasname) " = " SYMBOL_NAME(name)); \
85	91	_LIBUNWIND_ALIAS_VISIBILITY(SYMBOL_NAME(aliasname))
86		#elif defined(__ELF__) \|\| defined(_AIX)
	92	#elif defined(__ELF__) \|\| defined(_AIX) \|\| defined(__wasm__)
87	93	#define _LIBUNWIND_WEAK_ALIAS(name, aliasname) \
88	94	extern "C" _LIBUNWIND_EXPORT __typeof(name) aliasname \
89	95	__attribute__((weak, alias(#name)));
...	...	@@ -108,10 +114,6 @@
108	114	#define _LIBUNWIND_BUILD_SJLJ_APIS
109	115	#endif
110	116
111		#if defined(__i386__) \|\| defined(__x86_64__) \|\| defined(__powerpc__)
112		#define _LIBUNWIND_SUPPORT_FRAME_APIS
113		#endif
114
115	117	#if defined(__i386__) \|\| defined(__x86_64__) \|\| defined(__powerpc__) \|\| \
116	118	(!defined(__APPLE__) && defined(__arm__)) \|\| defined(__aarch64__) \|\| \
117	119	defined(__mips__) \|\| defined(__riscv) \|\| defined(__hexagon__) \|\| \
...	...	@@ -125,7 +127,7 @@
125	127	#if defined(_LIBUNWIND_REMEMBER_STACK_ALLOC) \|\| defined(__APPLE__) \|\| \
126	128	defined(__linux__) \|\| defined(__ANDROID__) \|\| defined(__MINGW32__) \|\| \
127	129	defined(_LIBUNWIND_IS_BAREMETAL)
128		#define _LIBUNWIND_REMEMBER_ALLOC(_size) alloca(_size)
	130	#define _LIBUNWIND_REMEMBER_ALLOC(_size) __builtin_alloca(_size)
129	131	#define _LIBUNWIND_REMEMBER_FREE(_ptr) \
130	132	do { \
131	133	} while (0)

lib/libunwind/src/libunwind.cpp+4-3

...	...	@@ -26,7 +26,7 @@
26	26	#include <sanitizer/asan_interface.h>
27	27	#endif
28	28
29		#if !defined(__USING_SJLJ_EXCEPTIONS__)
	29	#if !defined(__USING_SJLJ_EXCEPTIONS__) && !defined(__USING_WASM_EXCEPTIONS__)
30	30	#include "AddressSpace.hpp"
31	31	#include "UnwindCursor.hpp"
32	32
...	...	@@ -324,7 +324,7 @@ void __unw_add_dynamic_eh_frame_section(unw_word_t eh_frame_start) {
324	324	CFI_Parser<LocalAddressSpace>::CIE_Info cieInfo;
325	325	CFI_Parser<LocalAddressSpace>::FDE_Info fdeInfo;
326	326	auto p = (LocalAddressSpace::pint_t)eh_frame_start;
327		while (true) {
	327	while (LocalAddressSpace::sThisAddressSpace.get32(p)) {
328	328	if (CFI_Parser<LocalAddressSpace>::decodeFDE(
329	329	LocalAddressSpace::sThisAddressSpace, p, &fdeInfo, &cieInfo,
330	330	true) == NULL) {
...	...	@@ -347,7 +347,8 @@ void __unw_remove_dynamic_eh_frame_section(unw_word_t eh_frame_start) {
347	347	}
348	348
349	349	#endif // defined(_LIBUNWIND_SUPPORT_DWARF_UNWIND)
350		#endif // !defined(__USING_SJLJ_EXCEPTIONS__)
	350	#endif // !defined(__USING_SJLJ_EXCEPTIONS__) &&
	351	// !defined(__USING_WASM_EXCEPTIONS__)
351	352
352	353	#ifdef __APPLE__
353	354

src/libunwind.zig+1

...	...	@@ -164,6 +164,7 @@ const unwind_src_list = [_][]const u8{
164	164	"libunwind" ++ path.sep_str ++ "src" ++ path.sep_str ++ "UnwindLevel1.c",
165	165	"libunwind" ++ path.sep_str ++ "src" ++ path.sep_str ++ "UnwindLevel1-gcc-ext.c",
166	166	"libunwind" ++ path.sep_str ++ "src" ++ path.sep_str ++ "Unwind-sjlj.c",
	167	"libunwind" ++ path.sep_str ++ "src" ++ path.sep_str ++ "Unwind-wasm.c",
167	168	"libunwind" ++ path.sep_str ++ "src" ++ path.sep_str ++ "UnwindRegistersRestore.S",
168	169	"libunwind" ++ path.sep_str ++ "src" ++ path.sep_str ++ "UnwindRegistersSave.S",
169	170	"libunwind" ++ path.sep_str ++ "src" ++ path.sep_str ++ "Unwind_AIXExtras.cpp",