From: Easwaran Raman <eraman@google.com>
Date: Mon, 4 Jan 2016 23:32:28 +0000 (+0000)
Subject: Remove setting of inlinehint and cold attributes based on profile data
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=2edc5af5d22b08b138aecc949cc96f2ed6cadf1b;p=clang

Remove setting of inlinehint and cold attributes based on profile data

NFC. These hints are only used for inlining and the inliner now uses
the same criteria to identify hot and cold callees and set appropriate
thresholds without relying on these hints. Hence this removed code is
superfluous.

Differential Revision: http://reviews.llvm.org/D15726



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@256793 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/CodeGenPGO.cpp b/lib/CodeGen/CodeGenPGO.cpp
index 38774332f3..5ae861eab0 100644
--- a/lib/CodeGen/CodeGenPGO.cpp
+++ b/lib/CodeGen/CodeGenPGO.cpp
@@ -721,17 +721,7 @@ CodeGenPGO::applyFunctionAttributes(llvm::IndexedInstrProfReader *PGOReader,
   if (!haveRegionCounts())
     return;
 
-  uint64_t MaxFunctionCount = PGOReader->getMaximumFunctionCount();
   uint64_t FunctionCount = getRegionCount(nullptr);
-  if (FunctionCount >= (uint64_t)(0.3 * (double)MaxFunctionCount))
-    // Turn on InlineHint attribute for hot functions.
-    // FIXME: 30% is from preliminary tuning on SPEC, it may not be optimal.
-    Fn->addFnAttr(llvm::Attribute::InlineHint);
-  else if (FunctionCount <= (uint64_t)(0.01 * (double)MaxFunctionCount))
-    // Turn on Cold attribute for cold functions.
-    // FIXME: 1% is from preliminary tuning on SPEC, it may not be optimal.
-    Fn->addFnAttr(llvm::Attribute::Cold);
-
   Fn->setEntryCount(FunctionCount);
 }
 
diff --git a/test/Profile/c-attributes.c b/test/Profile/c-attributes.c
deleted file mode 100644
index 2dcc180624..0000000000
--- a/test/Profile/c-attributes.c
+++ /dev/null
@@ -1,48 +0,0 @@
-// Test that instrumentation based profiling sets function attributes correctly.
-
-// RUN: llvm-profdata merge %S/Inputs/c-attributes.proftext -o %t.profdata
-// RUN: %clang %s -o - -mllvm -disable-llvm-optzns -emit-llvm -S -fprofile-instr-use=%t.profdata | FileCheck %s
-
-extern int atoi(const char *);
-
-// CHECK: hot_100_percent(i32{{.*}}%i) [[HOT:#[0-9]+]]
-void hot_100_percent(int i) {
-  while (i > 0)
-    i--;
-}
-
-// CHECK: hot_40_percent(i32{{.*}}%i) [[HOT]]
-void hot_40_percent(int i) {
-  while (i > 0)
-    i--;
-}
-
-// CHECK: normal_func(i32{{.*}}%i) [[NORMAL:#[0-9]+]]
-void normal_func(int i) {
-  while (i > 0)
-    i--;
-}
-
-// CHECK: cold_func(i32{{.*}}%i) [[COLD:#[0-9]+]]
-void cold_func(int i) {
-  while (i > 0)
-    i--;
-}
-
-// CHECK: attributes [[HOT]] = { inlinehint nounwind {{.*}} }
-// CHECK: attributes [[NORMAL]] = { nounwind {{.*}} }
-// CHECK: attributes [[COLD]] = { cold nounwind {{.*}} }
-
-int main(int argc, const char *argv[]) {
-  int max = atoi(argv[1]);
-  int i;
-  for (i = 0; i < max; i++)
-    hot_100_percent(i);
-  for (i = 0; i < max * 4 / 10; i++)
-    hot_40_percent(i);
-  for (i = 0; i < max * 2 / 10; i++)
-    normal_func(i);
-  for (i = 0; i < max / 200; i++)
-    cold_func(i);
-  return 0;
-}
diff --git a/test/Profile/func-entry.c b/test/Profile/func-entry.c
index 32c20a2a45..1ecae601a4 100644
--- a/test/Profile/func-entry.c
+++ b/test/Profile/func-entry.c
@@ -5,10 +5,10 @@
 
 void foo(void);
 
-// CHECK: @foo() #0 !prof [[FOO:![0-9]+]]
+// CHECK: @foo() #{{[0-9]}} !prof [[FOO:![0-9]+]]
 void foo() { return; }
 
-// CHECK: @main() #1 !prof [[MAIN:![0-9]+]]
+// CHECK: @main() #{{[0-9]}} !prof [[MAIN:![0-9]+]]
 int main() {
   int i;
   for (i = 0; i < 10000; i++) foo();