[hwasan] Show sp in register dump.

[fmayer]

Format test properly.

[fmayer]

Require aarch64 rather than XFAIL x86.

[eugenis]

compiler-rt/lib/hwasan/hwasan_report.cpp

657

I'd rather put it in the last line of the dump, after x30.

compiler-rt/test/hwasan/TestCases/stack-pointer-report.c

14

I'd rather copy sp into a local variable and print it right here. It is not impossible that x11 would be in use at this point. SP does not normally change within a function (unless you do alloca or other weird things), so the copy does not have to be immediately before the fault.

15

this volatile does not do anything AFAIK - you'd need "z" itself to be volatile to force the memory access. This does not really matter at -O0 but still.

[eugenis]

compiler-rt/test/hwasan/TestCases/stack-pointer-report.c

14

In fact, update register-dump-read.c test instead of adding a new one.

[hctim]

compiler-rt/test/hwasan/TestCases/stack-pointer-report.c

14

-ffixed-x11 is another option but I like Evgenii's suggestion better.

[fmayer]

Change format, use existing test.

[fmayer]

Thanks!

compiler-rt/test/hwasan/TestCases/stack-pointer-report.c

14

I added it to register-dump-read.c, but used a register (and fixed-x11), because that is how the whole test is structured and it seemed simpler this way.

[hctim]

LGTM w/ nit.

compiler-rt/lib/hwasan/hwasan_report.cpp

682

I think (and agree with) @eugenis meant to be on the same line as x30.

[fmayer]

Move sp to last line rather than its own.

[eugenis]

LGTM

compiler-rt/lib/hwasan/hwasan_report.cpp

if (registers_frame)
     ReportRegisters(registers_frame, pc);
 
   ReportErrorSummary(bug_type, stack);
 }
 
 // See the frame breakdown defined in __hwasan_tag_mismatch (from
 // hwasan_tag_mismatch_aarch64.S).
 void ReportRegisters(uptr *frame, uptr pc) {
-  Printf("Registers where the failure occurred (pc %p):\n", pc);
+  // hwasan_check* reduces the stack pointer by 256, then __hwasan_tag_mismatch
+  // passes it to this function.
+  Printf("Registers where the failure occurred (pc %p, sp %p):\n", pc,
+         reinterpret_cast<u8 *>(frame) + 256);
 
   // We explicitly print a single line (4 registers/line) each iteration to
   // reduce the amount of logcat error messages printed. Each Printf() will
   // result in a new logcat line, irrespective of whether a newline is present,
   // and so we wish to reduce the number of Printf() calls we have to make.
   Printf("    x0  %016llx  x1  %016llx  x2  %016llx  x3  %016llx\n",
        frame[0], frame[1], frame[2], frame[3]);
   Printf("    x4  %016llx  x5  %016llx  x6  %016llx  x7  %016llx\n",
        frame[4], frame[5], frame[6], frame[7]);
   Printf("    x8  %016llx  x9  %016llx  x10 %016llx  x11 %016llx\n",
        frame[8], frame[9], frame[10], frame[11]);
   Printf("    x12 %016llx  x13 %016llx  x14 %016llx  x15 %016llx\n",
        frame[12], frame[13], frame[14], frame[15]);
   Printf("    x16 %016llx  x17 %016llx  x18 %016llx  x19 %016llx\n",
        frame[16], frame[17], frame[18], frame[19]);
   Printf("    x20 %016llx  x21 %016llx  x22 %016llx  x23 %016llx\n",
        frame[20], frame[21], frame[22], frame[23]);
   Printf("    x24 %016llx  x25 %016llx  x26 %016llx  x27 %016llx\n",
        frame[24], frame[25], frame[26], frame[27]);
   Printf("    x28 %016llx  x29 %016llx  x30 %016llx\n",
        frame[28], frame[29], frame[30]);
 }
 
 }  // namespace __hwasan
 
 void __hwasan_set_error_report_callback(void (*callback)(const char *)) {
   __hwasan::ScopedReport::SetErrorReportCallback(callback);
 }

compiler-rt/test/hwasan/TestCases/stack-pointer-report.c

+// RUN: %clang_hwasan -DSIZE=2 -O0 %s -o %t && not %run %t 2>&1 | FileCheck %s
+
+// Register reporting is not supported on x86_64.
+// XFAIL: x86_64
+
+#include <sanitizer/hwasan_interface.h>
+#include <stdlib.h>
+
+__attribute__((noinline)) void f() {
+  char z[SIZE];
+  // Copy stack pointer just before the fault into x11, so we can compare that
+  // x11 is equal to the sp in the report.
+  __asm __volatile__("mov x11, sp");
+  volatile char sink = z[SIZE];
+}
+
+int main() {
+  f();
+}
+
+// CHECK: sp 0x[[STACK:[0-9a-f]+]]
+// CHECK: x11 {{[0]*}}{{[0-9a-f]+}}[[STACK]]