[hwasan] print globals in symbolizer-friendly format.

[eugenis]

LGTM

My only concern is that an unsuspecting tool will symbolize this as code, not data location. As I understand, these are mostly equivalent when there is no line info for the address, which is the most common case. See the difference between SymbolizableObjectFile::symbolizeCode and symbolizeData. This change looks an improvement.

@hctim FYI

[pcc]

compiler-rt/lib/hwasan/hwasan_report.cpp

356

Should there be a #0 here as well?

[fmayer]

fix format

compiler-rt/lib/hwasan/hwasan_report.cpp

if (sym->SymbolizeData(mem, &info) && info.start) {
           candidate == left ? untagged_addr - (info.start + info.size)
                             : info.start - untagged_addr,
           candidate == left ? "right" : "left", info.size, info.name,
           info.start, info.start + info.size, module_name);
     } else {
       uptr size = GetGlobalSizeFromDescriptor(mem);
       if (size == 0)
         // We couldn't find the size of the global from the descriptors.
-        Printf("%p is located to the %s of a global variable in (%s+0x%x)\n",
-               untagged_addr, candidate == left ? "right" : "left", module_name,
-               module_address);
+        Printf(
+            "%p is located to the %s of a global variable in "
+            "\n    #0 0x%x (%s+0x%x)\n",
+            untagged_addr, candidate == left ? "right" : "left", mem,
+            module_name, module_address);
       else
         Printf(
             "%p is located to the %s of a %zd-byte global variable in "
-            "(%s+0x%x)\n",
-            untagged_addr, candidate == left ? "right" : "left", size,
+            "\n    #0 0x%x (%s+0x%x)\n",
+            untagged_addr, candidate == left ? "right" : "left", size, mem,
             module_name, module_address);
     }
     Printf("%s", d.Default());
   }
 }
 
 void PrintAddressDescription(
     uptr tagged_addr, uptr access_size,

compiler-rt/test/hwasan/TestCases/global.c

 // RUN: %clang_hwasan %s -o %t
 // RUN: %run %t 0
 // RUN: not %run %t 1 2>&1 | FileCheck --check-prefixes=CHECK,RSYM %s
 // RUN: not %env_hwasan_opts=symbolize=0 %run %t 1 2>&1 | FileCheck --check-prefixes=CHECK,RNOSYM %s
 // RUN: not %run %t -1 2>&1 | FileCheck --check-prefixes=CHECK,LSYM %s
 // RUN: not %env_hwasan_opts=symbolize=0 %run %t -1 2>&1 | FileCheck --check-prefixes=CHECK,LNOSYM %s
 
 // REQUIRES: pointer-tagging
 
 int x = 1;
 
 int main(int argc, char **argv) {
   // CHECK: Cause: global-overflow
   // RSYM: is located 0 bytes to the right of 4-byte global variable x {{.*}} in {{.*}}global.c.tmp
-  // RNOSYM: is located to the right of a 4-byte global variable in ({{.*}}global.c.tmp+{{.*}})
+  // RNOSYM: is located to the right of a 4-byte global variable in
+  // RNOSYM-NEXT: #0 0x{{.*}} ({{.*}}global.c.tmp+{{.*}})
   // LSYM: is located 4 bytes to the left of 4-byte global variable x {{.*}} in {{.*}}global.c.tmp
-  // LNOSYM: is located to the left of a 4-byte global variable in ({{.*}}global.c.tmp+{{.*}})
+  // LNOSYM: is located to the left of a 4-byte global variable in
+  // LNOSYM-NEXT: #0 0x{{.*}} ({{.*}}global.c.tmp+{{.*}})
   // CHECK-NOT: can not describe
   (&x)[atoi(argv[1])] = 1;
 }