Determine callee's hotness and adjust threshold based on that. NFC.

This uses the same criteria used in CFE's CodeGenPGO to identify hot and cold
callees and uses values of inlinehint-threshold and inlinecold-threshold
respectively as the thresholds for such callees.

Differential Revision: http://reviews.llvm.org/D15245

llvm-svn: 256222

2 files changed, 78 insertions, 0 deletions

diff --git a/llvm/test/Transforms/Inline/inline-cold-callee.ll b/llvm/test/Transforms/Inline/inline-cold-callee.ll
new file mode 100644
index 00000000000..1fd9f105db5
--- /dev/null
+++ b/llvm/test/Transforms/Inline/inline-cold-callee.ll
@@ -0,0 +1,39 @@
+; RUN: opt < %s -inline  -inlinecold-threshold=0 -S | FileCheck %s
+
+; This tests that a cold callee gets the (lower) inlinecold-threshold even without
+; Cold hint and does not get inlined because the cost exceeds the inlinecold-threshold.
+; A callee with identical body does gets inlined because cost fits within the
+; inline-threshold
+
+define i32 @callee1(i32 %x) !prof !1 {
+  %x1 = add i32 %x, 1
+  %x2 = add i32 %x1, 1
+  %x3 = add i32 %x2, 1
+
+  ret i32 %x3
+}
+
+define i32 @callee2(i32 %x) !prof !2 {
+; CHECK-LABEL: @callee2(
+  %x1 = add i32 %x, 1
+  %x2 = add i32 %x1, 1
+  %x3 = add i32 %x2, 1
+
+  ret i32 %x3
+}
+
+define i32 @caller2(i32 %y1) !prof !2 {
+; CHECK-LABEL: @caller2(
+; CHECK: call i32 @callee2
+; CHECK-NOT: call i32 @callee1
+; CHECK: ret i32 %x3.i
+  %y2 = call i32 @callee2(i32 %y1)
+  %y3 = call i32 @callee1(i32 %y2)
+  ret i32 %y3
+}
+
+!llvm.module.flags = !{!0}
+!0 = !{i32 1, !"MaxFunctionCount", i32 1000}
+!1 = !{!"function_entry_count", i64 100}
+!2 = !{!"function_entry_count", i64 1}
+
diff --git a/llvm/test/Transforms/Inline/inline-hot-callee.ll b/llvm/test/Transforms/Inline/inline-hot-callee.ll
new file mode 100644
index 00000000000..93ea9d43c78
--- /dev/null
+++ b/llvm/test/Transforms/Inline/inline-hot-callee.ll
@@ -0,0 +1,39 @@
+; RUN: opt < %s -inline -inline-threshold=0 -inlinehint-threshold=100 -S | FileCheck %s
+
+; This tests that a hot callee gets the (higher) inlinehint-threshold even without
+; inline hints and gets inlined because the cost is less than inlinehint-threshold.
+; A cold callee with identical body does not get inlined because cost exceeds the
+; inline-threshold
+
+define i32 @callee1(i32 %x) !prof !1 {
+  %x1 = add i32 %x, 1
+  %x2 = add i32 %x1, 1
+  %x3 = add i32 %x2, 1
+
+  ret i32 %x3
+}
+
+define i32 @callee2(i32 %x) !prof !2 {
+; CHECK-LABEL: @callee2(
+  %x1 = add i32 %x, 1
+  %x2 = add i32 %x1, 1
+  %x3 = add i32 %x2, 1
+
+  ret i32 %x3
+}
+
+define i32 @caller2(i32 %y1) !prof !2 {
+; CHECK-LABEL: @caller2(
+; CHECK: call i32 @callee2
+; CHECK-NOT: call i32 @callee1
+; CHECK: ret i32 %x3.i
+  %y2 = call i32 @callee2(i32 %y1)
+  %y3 = call i32 @callee1(i32 %y2)
+  ret i32 %y3
+}
+
+!llvm.module.flags = !{!0}
+!0 = !{i32 1, !"MaxFunctionCount", i32 10}
+!1 = !{!"function_entry_count", i64 10}
+!2 = !{!"function_entry_count", i64 1}
+