Commit 5c7f2ab011f9c1cd522ab76a674d0acc5f397041 | zig

author	Kenta Iwasaki <kenta@lithdew.net> 2021-12-20 00:30:49+09:00
committer	Andrew Kelley <andrew@ziglang.org> 2021-12-19 23:22:05-08:00
log	5c7f2ab011f9c1cd522ab76a674d0acc5f397041
tree	a1f974af9f30bc09f32f82e189b58f6f73653c14
parent	16b753549702e2fc662491a468dd3323e8a51042

stage1: deal with BPF not supporting @returnAddress()

Make `@returnAddress()` return for the BPF target, as the BPF target for
the time being does not support probing for the return address. Stack
traces for the general purpose allocator for the BPF target is also set
to not be captured.

4 files changed, 11 insertions(+), 1 deletions(-)

lib
- std
  - heap
    general_purpose_allocator.zig
src
- stage1

lib/std/heap/general_purpose_allocator.zig+5

...	...	@@ -118,6 +118,11 @@ const sys_can_stack_trace = switch (builtin.cpu.arch) {
118	118	.wasm64,
119	119	=> builtin.os.tag == .emscripten,
120	120
	121	// `@returnAddress()` is unsupported in LLVM 13.
	122	.bpfel,
	123	.bpfeb,
	124	=> false,
	125
121	126	else => true,
122	127	};
123	128	const default_test_stack_trace_frames: usize = if (builtin.is_test) 8 else 4;

src/stage1/codegen.cpp+1-1

...	...	@@ -6208,7 +6208,7 @@ static LLVMValueRef ir_render_breakpoint(CodeGen g, Stage1Air executable, Stag
6208	6208	static LLVMValueRef ir_render_return_address(CodeGen g, Stage1Air executable,
6209	6209	Stage1AirInstReturnAddress *instruction)
6210	6210	{
6211		if (target_is_wasm(g->zig_target) && g->zig_target->os != OsEmscripten) {
	6211	if ((target_is_wasm(g->zig_target) && g->zig_target->os != OsEmscripten) \|\| target_is_bpf(g->zig_target)) {
6212	6212	// I got this error from LLVM 10:
6213	6213	// "Non-Emscripten WebAssembly hasn't implemented __builtin_return_address"
6214	6214	return LLVMConstNull(get_llvm_type(g, instruction->base.value->type));

src/stage1/target.cpp+4

...	...	@@ -940,6 +940,10 @@ bool target_is_wasm(const ZigTarget *target) {
940	940	return target->arch == ZigLLVM_wasm32 \|\| target->arch == ZigLLVM_wasm64;
941	941	}
942	942
	943	bool target_is_bpf(const ZigTarget *target) {
	944	return target->arch == ZigLLVM_bpfel \|\| target->arch == ZigLLVM_bpfeb;
	945	}
	946
943	947	ZigLLVM_EnvironmentType target_default_abi(ZigLLVM_ArchType arch, Os os) {
944	948	if (arch == ZigLLVM_wasm32 \|\| arch == ZigLLVM_wasm64) {
945	949	return ZigLLVM_Musl;

src/stage1/target.hpp+1

...	...	@@ -75,6 +75,7 @@ bool target_allows_addr_zero(const ZigTarget *target);
75	75	bool target_has_valgrind_support(const ZigTarget *target);
76	76	bool target_os_is_darwin(Os os);
77	77	bool target_is_wasm(const ZigTarget *target);
	78	bool target_is_bpf(const ZigTarget *target);
78	79	bool target_is_riscv(const ZigTarget *target);
79	80	bool target_is_sparc(const ZigTarget *target);
80	81	bool target_is_android(const ZigTarget *target);