[esan|wset] Iterate all memory to compute the total working set

Summary:
Adds iteration of all application memory in an efficient manner using
shadow faults.  Shadow memory starts out inaccessible and we mark it
writable one page at a time on each fault when the instrumentation touches
it.  This allows iteration over just the mapped shadow memory, saving
significant time.

Adds a process-end iteration and pretty-printing of the final result.

Adds a new test and updates the existing tests.

Reviewers: aizatsky, filcab

Subscribers: vitalybuka, zhaoqin, kcc, eugenis, llvm-commits, kubabrecka

Differential Revision: http://reviews.llvm.org/D20578

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@271277 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 32 insertions, 2 deletions

diff --git a/test/esan/TestCases/workingset-memset.cpp b/test/esan/TestCases/workingset-memset.cpp
index a0c36e3ae..9c972ec7a 100644
--- a/test/esan/TestCases/workingset-memset.cpp
+++ b/test/esan/TestCases/workingset-memset.cpp
@@ -16,6 +16,5 @@ int main(int argc, char **argv) {
     memset((char *)p + 63*i, i, 63*i);
   munmap(p, size);
   return 0;
-  // FIXME: once the memory scan and size report is in place add it here.
-  // CHECK: {{.*}}EfficiencySanitizer is not finished: nothing yet to report
+  // CHECK: {{.*}} EfficiencySanitizer: the total working set size: 77 KB (12{{[0-9]+}} cache lines)
 }
diff --git a/test/esan/TestCases/workingset-signal-posix.cpp b/test/esan/TestCases/workingset-signal-posix.cpp
index c0245760c..fe7ced0cc 100644
--- a/test/esan/TestCases/workingset-signal-posix.cpp
+++ b/test/esan/TestCases/workingset-signal-posix.cpp
@@ -57,3 +57,4 @@ int main(int argc, char **argv) {
 // CHECK-NEXT: Past longjmp for signal
 // CHECK-NEXT: Handling SIGSEGV for sigaction
 // CHECK-NEXT: Past longjmp for sigaction
+// CHECK:      {{.*}} EfficiencySanitizer: the total working set size: {{[0-9][0-9][0-9]}} Bytes ({{[0-9][0-9]}} cache lines)
diff --git a/test/esan/TestCases/workingset-simple.cpp b/test/esan/TestCases/workingset-simple.cpp
new file mode 100644
index 000000000..c8a2d52e7
--- /dev/null
+++ b/test/esan/TestCases/workingset-simple.cpp
@@ -0,0 +1,30 @@
+// RUN: %clang_esan_wset -O0 %s -o %t 2>&1
+// RUN: %run %t 2>&1 | FileCheck %s
+
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <assert.h>
+
+const int size = 0x1 << 25; // 523288 cache lines
+const int line_size = 64;
+
+int main(int argc, char **argv) {
+  char *bufA = (char *)malloc(sizeof(char) * line_size);
+  char bufB[64];
+  char *bufC = (char *)mmap(0, size, PROT_READ | PROT_WRITE,
+                            MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+  bufA[0] = 0;
+  // This additional access to the same line should not increase the line
+  // count: but it's difficult to make a non-flaky test that measures the
+  // lines down to the ones digit so right now we're not really testing that.
+  // If we add a heap-only mode we may be able to be more precise.
+  bufA[1] = 0;
+  bufB[33] = 1;
+  for (int i = 0; i < size; i += line_size)
+    bufC[i] = 0;
+  free(bufA);
+  munmap(bufC, 0x4000);
+  // CHECK: {{.*}} EfficiencySanitizer: the total working set size: 32 MB (524{{[0-9][0-9][0-9]}} cache lines)
+  return 0;
+}