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-rw-r--r--lib/sanitizer_common/sanitizer_stacktrace_sparc.cpp85
1 files changed, 85 insertions, 0 deletions
diff --git a/lib/sanitizer_common/sanitizer_stacktrace_sparc.cpp b/lib/sanitizer_common/sanitizer_stacktrace_sparc.cpp
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+++ b/lib/sanitizer_common/sanitizer_stacktrace_sparc.cpp
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+//===-- sanitizer_stacktrace_sparc.cpp ------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is shared between AddressSanitizer and ThreadSanitizer
+// run-time libraries.
+//
+// Implemention of fast stack unwinding for Sparc.
+//===----------------------------------------------------------------------===//
+
+#if defined(__sparc__)
+
+#if defined(__arch64__) || defined(__sparcv9)
+#define STACK_BIAS 2047
+#else
+#define STACK_BIAS 0
+#endif
+
+#include "sanitizer_common.h"
+#include "sanitizer_stacktrace.h"
+
+namespace __sanitizer {
+
+void BufferedStackTrace::UnwindFast(uptr pc, uptr bp, uptr stack_top,
+ uptr stack_bottom, u32 max_depth) {
+ // TODO(yln): add arg sanity check for stack_top/stack_bottom
+ CHECK_GE(max_depth, 2);
+ const uptr kPageSize = GetPageSizeCached();
+#if defined(__GNUC__)
+ // __builtin_return_address returns the address of the call instruction
+ // on the SPARC and not the return address, so we need to compensate.
+ trace_buffer[0] = GetNextInstructionPc(pc);
+#else
+ trace_buffer[0] = pc;
+#endif
+ size = 1;
+ if (stack_top < 4096) return; // Sanity check for stack top.
+ // Flush register windows to memory
+#if defined(__sparc_v9__) || defined(__sparcv9__) || defined(__sparcv9)
+ asm volatile("flushw" ::: "memory");
+#else
+ asm volatile("ta 3" ::: "memory");
+#endif
+ // On the SPARC, the return address is not in the frame, it is in a
+ // register. There is no way to access it off of the current frame
+ // pointer, but it can be accessed off the previous frame pointer by
+ // reading the value from the register window save area.
+ uptr prev_bp = GET_CURRENT_FRAME();
+ uptr next_bp = prev_bp;
+ unsigned int i = 0;
+ while (next_bp != bp && IsAligned(next_bp, sizeof(uhwptr)) && i++ < 8) {
+ prev_bp = next_bp;
+ next_bp = (uptr)((uhwptr *)next_bp)[14] + STACK_BIAS;
+ }
+ if (next_bp == bp)
+ bp = prev_bp;
+ // Lowest possible address that makes sense as the next frame pointer.
+ // Goes up as we walk the stack.
+ uptr bottom = stack_bottom;
+ // Avoid infinite loop when frame == frame[0] by using frame > prev_frame.
+ while (IsValidFrame(bp, stack_top, bottom) && IsAligned(bp, sizeof(uhwptr)) &&
+ size < max_depth) {
+ uhwptr pc1 = ((uhwptr *)bp)[15];
+ // Let's assume that any pointer in the 0th page is invalid and
+ // stop unwinding here. If we're adding support for a platform
+ // where this isn't true, we need to reconsider this check.
+ if (pc1 < kPageSize)
+ break;
+ if (pc1 != pc) {
+ // %o7 contains the address of the call instruction and not the
+ // return address, so we need to compensate.
+ trace_buffer[size++] = GetNextInstructionPc((uptr)pc1);
+ }
+ bottom = bp;
+ bp = (uptr)((uhwptr *)bp)[14] + STACK_BIAS;
+ }
+}
+
+} // namespace __sanitizer
+
+#endif // !defined(__sparc__)