[hwasan] Fix unsymbolized stack history printing.

[eugenis]

Summary

When symbols are unavailable, the current code prints

sp: ... pc: ... (null) (null)

instead of module name + offset.

Change the output to include module name and offset, and also to match
the regular sanitizer stack trace format so that it is recognized by
symbolize.py out of the box.

[pcc]

LGTM

compiler-rt/trunk/lib/hwasan/hwasan_report.cc

if (t->AddrIsInStack(untagged_addr)) {
       for (uptr i = 0; i < frames; i++) {
         uptr record = (*sa)[i];
         if (!record)
           break;
         uptr sp = (record >> 48) << 4;
         uptr pc_mask = (1ULL << 48) - 1;
         uptr pc = record & pc_mask;
         if (SymbolizedStack *frame = Symbolizer::GetOrInit()->SymbolizePC(pc)) {
-          frame_desc.append(" sp: 0x%zx pc: %p ", sp, pc);
-          RenderFrame(&frame_desc, "in %f %s:%l\n", 0, frame->info,
+          frame_desc.append(" sp: 0x%zx ", sp);
+          RenderFrame(&frame_desc, "#%n %p %F %L\n", 0, frame->info,
                       common_flags()->symbolize_vs_style,
                       common_flags()->strip_path_prefix);
           frame->ClearAll();
           if (auto Descr = GetStackFrameDescr(pc))
             frame_desc.append("  %s\n", Descr);
         }
         Printf("%s", frame_desc.data());
         frame_desc.clear();

compiler-rt/trunk/test/hwasan/TestCases/stack-uar.c

 // Tests use-after-return detection and reporting.
 // RUN: %clang_hwasan -O0 -fno-discard-value-names %s -o %t && not %run %t 2>&1 | FileCheck %s
+// RUN: %clang_hwasan -O0 -fno-discard-value-names %s -o %t && not %env_hwasan_opts=symbolize=0 %run %t 2>&1 | FileCheck %s --check-prefix=NOSYM
 
 // REQUIRES: stable-runtime
 
 void USE(void *x) { // pretend_to_do_something(void *x)
   __asm__ __volatile__("" : : "r" (x) : "memory");
 }
 
 __attribute__((noinline))
int main() {
   // CHECK: 16 CCC
   // CHECK: Unrelated2
   // CHECK: 12 BB
   // CHECK: Unrelated1
   // CHECK: 8 A
   // CHECK: buggy
   // CHECK: 4096 zzz
 
+  // NOSYM: Previously allocated frames:
+  // NOSYM-NEXT: sp: 0x{{.*}} #0 0x{{.*}} ({{.*}}/stack-uar.c.tmp+0x{{.*}}){{$}}
+  // NOSYM-NEXT: 16 CCC;
+
   // CHECK: SUMMARY: HWAddressSanitizer: tag-mismatch {{.*}} in main
 }