Attach maximum function count to Module when using PGO mode.

This sets the maximum entry count among all functions in the program to the module using module flags. This allows the optimizer to use this information.

Differential Revision: http://reviews.llvm.org/D15163


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@255918 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 50 insertions, 0 deletions

diff --git a/test/Profile/Inputs/max-function-count.proftext b/test/Profile/Inputs/max-function-count.proftext
new file mode 100644
index 0000000000..c744f7af9d
--- /dev/null
+++ b/test/Profile/Inputs/max-function-count.proftext
@@ -0,0 +1,26 @@
+begin
+# Func Hash:
+10
+# Num Counters:
+2
+# Counter Values:
+1
+0
+
+main
+# Func Hash:
+0
+# Num Counters:
+1
+# Counter Values:
+1
+
+end
+# Func Hash:
+10
+# Num Counters:
+2
+# Counter Values:
+2
+2
+
diff --git a/test/Profile/max-function-count.c b/test/Profile/max-function-count.c
new file mode 100644
index 0000000000..39490d7b27
--- /dev/null
+++ b/test/Profile/max-function-count.c
@@ -0,0 +1,24 @@
+// Test that maximum function counts are set correctly.
+
+// RUN: llvm-profdata merge %S/Inputs/max-function-count.proftext -o %t.profdata
+// RUN: %clang %s -o - -mllvm -disable-llvm-optzns -emit-llvm -S -fprofile-instr-use=%t.profdata | FileCheck %s
+//
+int begin(int i) {
+  if (i)
+    return 0;
+  return 1;
+}
+
+int end(int i) {
+  if (i)
+    return 0;
+  return 1;
+}
+
+int main(int argc, const char *argv[]) {
+  begin(0);
+  end(1);
+  end(1);
+  return 0;
+}
+// CHECK: !{{[0-9]+}} = !{i32 1, !"MaxFunctionCount", i32 2}