diff --git a/lib/std/debug.zig b/lib/std/debug.zig index f32c1a6156..74fb95ffa8 100644 --- a/lib/std/debug.zig +++ b/lib/std/debug.zig @@ -360,14 +360,24 @@ pub const StackIterator = struct { }; } - // Negative offset of the saved BP wrt the frame pointer. + // Offset of the saved BP wrt the frame pointer. const fp_offset = if (builtin.arch.isRISCV()) // On RISC-V the frame pointer points to the top of the saved register // area, on pretty much every other architecture it points to the stack // slot where the previous frame pointer is saved. 2 * @sizeOf(usize) + else if (builtin.arch.isSPARC()) + // On SPARC the previous frame pointer is stored at 14 slots past %fp+BIAS. + 14 * @sizeOf(usize) else 0; + + const fp_bias = if (builtin.arch.isSPARC()) + // On SPARC frame pointers are biased by a constant. + 2047 + else + 0; + // Positive offset of the saved PC wrt the frame pointer. const pc_offset = if (builtin.arch == .powerpc64le) 2 * @sizeOf(usize) @@ -388,13 +398,17 @@ pub const StackIterator = struct { } fn next_internal(self: *StackIterator) ?usize { - const fp = math.sub(usize, self.fp, fp_offset) catch return null; + const fp = if (builtin.arch.isSPARC()) + // On SPARC the offset is positive. (!) + math.add(usize, self.fp, fp_offset) catch return null + else + math.sub(usize, self.fp, fp_offset) catch return null; // Sanity check. if (fp == 0 or !mem.isAligned(fp, @alignOf(usize))) return null; - const new_fp = @intToPtr(*const usize, fp).*; + const new_fp = math.add(usize, @intToPtr(*const usize, fp).*, fp_bias) catch return null; // Sanity check: the stack grows down thus all the parent frames must be // be at addresses that are greater (or equal) than the previous one. diff --git a/src/stage1/codegen.cpp b/src/stage1/codegen.cpp index 7f8b1884bd..97daf249b1 100644 --- a/src/stage1/codegen.cpp +++ b/src/stage1/codegen.cpp @@ -4153,7 +4153,15 @@ static LLVMValueRef gen_frame_size(CodeGen *g, LLVMValueRef fn_val) { LLVMValueRef casted_fn_val = LLVMBuildBitCast(g->builder, fn_val, ptr_usize_llvm_type, ""); LLVMValueRef negative_one = LLVMConstInt(LLVMInt32Type(), -1, true); LLVMValueRef prefix_ptr = LLVMBuildInBoundsGEP(g->builder, casted_fn_val, &negative_one, 1, ""); - return LLVMBuildLoad(g->builder, prefix_ptr, ""); + LLVMValueRef load_inst = LLVMBuildLoad(g->builder, prefix_ptr, ""); + + // Some architectures (e.g SPARCv9) has different alignment requirements between a + // function/usize pointer and also require all loads to be aligned. + // On those architectures, not explicitly setting the alignment will lead into @frameSize + // generating usize-aligned load instruction that could crash if the function pointer + // happens to be not usize-aligned. + LLVMSetAlignment(load_inst, 1); + return load_inst; } static void gen_init_stack_trace(CodeGen *g, LLVMValueRef trace_field_ptr, LLVMValueRef addrs_field_ptr) {