[llvm-commits] [compiler-rt] r169474 - in /compiler-rt/trunk/lib/sanitizer_common: sanitizer_common.cc sanitizer_common.h tests/sanitizer_common_test.cc

[Kostya Serebryany]

Author: kcc
Date: Thu Dec  6 00:10:31 2012
New Revision: 169474

URL: http://llvm.org/viewvc/llvm-project?rev=169474&view=rev
Log:
[tsan] add MmapAlignedOrDie

Modified:
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.cc
    compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h
    compiler-rt/trunk/lib/sanitizer_common/tests/sanitizer_common_test.cc

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.cc?rev=169474&r1=169473&r2=169474&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.cc Thu Dec  6 00:10:31 2012
@@ -155,6 +155,27 @@
   }
 }
 
+// We want to map a chunk of address space aligned to 'alignment'.
+// We do it by maping a bit more and then unmaping redundant pieces.
+// We probably can do it with fewer syscalls in some OS-dependent way.
+void *MmapAlignedOrDie(uptr size, uptr alignment, const char *mem_type) {
+  uptr PageSize = GetPageSizeCached();
+  CHECK(IsPowerOfTwo(size));
+  CHECK(IsPowerOfTwo(alignment));
+  uptr map_size = size + alignment;
+  uptr map_res = (uptr)MmapOrDie(map_size, mem_type);
+  uptr map_end = map_res + map_size;
+  uptr res = map_res;
+  if (res & (alignment - 1))  // Not aligned.
+    res = (map_res + alignment) & ~ (alignment - 1);
+  uptr end = res + size;
+  if (res != map_res)
+    UnmapOrDie((void*)map_res, res - map_res);
+  if (end != map_end)
+    UnmapOrDie((void*)end, map_end - end);
+  return (void*)res;
+}
+
 }  // namespace __sanitizer
 
 using namespace __sanitizer;  // NOLINT

Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h?rev=169474&r1=169473&r2=169474&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_common.h Thu Dec  6 00:10:31 2012
@@ -45,6 +45,8 @@
 void UnmapOrDie(void *addr, uptr size);
 void *MmapFixedNoReserve(uptr fixed_addr, uptr size);
 void *Mprotect(uptr fixed_addr, uptr size);
+// Map aligned chunk of address space; size and alignment are powers of two.
+void *MmapAlignedOrDie(uptr size, uptr alignment, const char *mem_type);
 // Used to check if we can map shadow memory to a fixed location.
 bool MemoryRangeIsAvailable(uptr range_start, uptr range_end);
 

Modified: compiler-rt/trunk/lib/sanitizer_common/tests/sanitizer_common_test.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/tests/sanitizer_common_test.cc?rev=169474&r1=169473&r2=169474&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/tests/sanitizer_common_test.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/tests/sanitizer_common_test.cc Thu Dec  6 00:10:31 2012
@@ -63,4 +63,19 @@
   EXPECT_TRUE(IsSorted(array, 2));
 }
 
+TEST(SanitizerCommon, MmapAlignedOrDie) {
+  uptr PageSize = GetPageSizeCached();
+  for (uptr size = 1; size <= 32; size *= 2) {
+    for (uptr alignment = 1; alignment <= 32; alignment *= 2) {
+      for (int iter = 0; iter < 100; iter++) {
+        uptr res = (uptr)MmapAlignedOrDie(
+            size * PageSize, alignment * PageSize, "MmapAlignedOrDieTest");
+        EXPECT_EQ(0U, res % (alignment * PageSize));
+        memset((void*)res, 1, size * PageSize);
+        UnmapOrDie((void*)res, size * PageSize);
+      }
+    }
+  }
+}
+
 }  // namespace sanitizer