[profile] Fix value profile runtime merging issues

This patch fixes the following issues:
(1) The strong definition of the merge hook function was not working which
breaks the online value profile merging. This patch removes the weak
attribute of VPMergeHook and assigns the value dynamically.
(2) Truncate the proifle file so that we don't have garbage data at the end of
the file.
(3) Add new __llvm_profile_instrument_target_value() interface to do the value
profile update in batch. This is needed as the original incremental by 1
in __llvm_profile_instrument_target() is too slow for online merge.

Differential Revision: https://reviews.llvm.org/D44847


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@328987 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 79 insertions, 0 deletions

diff --git a/test/profile/instrprof-value-merge.c b/test/profile/instrprof-value-merge.c
new file mode 100644
index 000000000..902430a4a
--- /dev/null
+++ b/test/profile/instrprof-value-merge.c
@@ -0,0 +1,79 @@
+// RUN: %clang_pgogen -o %t -O3 %s
+// RUN: rm -rf %t.profdir
+// RUN: env LLVM_PROFILE_FILE=%t.profdir/default_%m.profraw %run %t
+// RUN: env LLVM_PROFILE_FILE=%t.profdir/default_%m.profraw %run %t
+// RUN: env LLVM_PROFILE_FILE=%t.profdir/default_%m.profraw %run %t
+// RUN: env LLVM_PROFILE_FILE=%t.profdir/default_%m.profraw %run %t 1
+// RUN: env LLVM_PROFILE_FILE=%t.profdir/default_%m.profraw %run %t 1
+// RUN: llvm-profdata show -counts -function=main -ic-targets -memop-sizes %t.profdir/default_*.profraw | FileCheck %s
+
+#include <string.h>
+
+void (*f0)();
+void (*f1)();
+void (*f2)();
+
+char dst[200];
+char src[200];
+volatile int n;
+
+__attribute__((noinline)) void foo() {}
+
+__attribute__((noinline)) void bar() {
+  f0 = foo;
+  f1 = foo;
+  f2 = foo;
+  n = 4;
+}
+int main(int argc, char *argv[]) {
+  int i;
+  bar();
+  if (argc == 1) {
+    f0();
+    for (i = 0; i < 9; i++)
+      f1();
+    for (i = 0; i < 99; i++)
+      f2();
+  } else {
+    memcpy((void *)dst, (void *)src, n);
+    for (i = 0; i < 6; i++)
+      memcpy((void *)(dst + 2), (void *)src, n + 1);
+    for (i = 0; i < 66; i++)
+      memcpy((void *)(dst + 9), (void *)src, n + 2);
+  }
+}
+
+// CHECK: Counters:
+// CHECK:   main:
+// CHECK:     Hash: 0x00030012a7ab6e87
+// CHECK:     Counters: 6
+// CHECK:     Indirect Call Site Count: 3
+// CHECK:     Number of Memory Intrinsics Calls: 3
+// CHECK:     Block counts: [27, 297, 12, 132, 3, 2]
+// CHECK:     Indirect Target Results:
+// CHECK:         [ 0, foo, 3 ]
+// CHECK:         [ 1, foo, 27 ]
+// CHECK:         [ 2, foo, 297 ]
+// CHECK:     Memory Intrinsic Size Results:
+// CHECK:         [ 0, 4, 2 ]
+// CHECK:         [ 1, 5, 12 ]
+// CHECK:         [ 2, 6, 132 ]
+// CHECK: Instrumentation level: IR
+// CHECK: Functions shown: 1
+// CHECK: Total functions: 3
+// CHECK: Maximum function count: 327
+// CHECK: Maximum internal block count: 297
+// CHECK: Statistics for indirect call sites profile:
+// CHECK:   Total number of sites: 3
+// CHECK:   Total number of sites with values: 3
+// CHECK:   Total number of profiled values: 3
+// CHECK:   Value sites histogram:
+// CHECK:         NumTargets, SiteCount
+// CHECK:         1, 3
+// CHECK: Statistics for memory intrinsic calls sizes profile:
+// CHECK:   Total number of sites: 3
+// CHECK:   Total number of sites with values: 3
+// CHECK:   Total number of profiled values: 3
+// CHECK:   Value sites histogram:
+// CHECK:         NumTargets, SiteCount
+// CHECK:         1, 3