Print out DebugCounter info with -print-debug-counter

Summary:
This patch will print out {Counter, Skip, StopAfter} info of all passes which have DebugCounter set at destruction.

It can be used to monitor how many times does certain transformation happen in a pass, and also help check if -debug-counter option is set correctly.

Please refer to this [[ http://lists.llvm.org/pipermail/llvm-dev/2018-July/124722.html  | thread ]] for motivation.

Reviewers: george.burgess.iv, davide, greened

Reviewed By: greened

Subscribers: kristina, llozano, mgorny, llvm-commits, mgrang

Differential Revision: https://reviews.llvm.org/D50031

llvm-svn: 345085

1 files changed, 30 insertions, 0 deletions

diff --git a/llvm/test/Other/print-debug-counter.ll b/llvm/test/Other/print-debug-counter.ll
new file mode 100644
index 000000000000..ffd197197d85
--- /dev/null
+++ b/llvm/test/Other/print-debug-counter.ll
@@ -0,0 +1,30 @@
+; RUN: opt -S -debug-counter=early-cse-skip=1,early-cse-count=1 -early-cse \
+; RUN:        -debug-counter=newgvn-vn-skip=1,newgvn-vn-count=2 -newgvn \
+; RUN:        -instcombine -print-debug-counter < %s 2>&1 | FileCheck %s
+;; Test debug counter prints correct info in right order.
+; CHECK-LABEL: Counters and values:
+; CHECK:       early-cse
+; CHECK-SAME:  {4,1,1}
+; CHECK:       instcombine-visit
+; CHECK-SAME:  {12,0,-1}
+; CHECK:       newgvn-vn
+; CHECK-SAME:  {9,1,2}
+define i32 @f1(i32 %a, i32 %b) {
+bb:
+  %add1 = add i32 %a, %b
+  %add2 = add i32 %a, %b
+  %add3 = add i32 %a, %b
+  %add4 = add i32 %a, %b
+  %ret1 = add i32 %add1, %add2
+  %ret2 = add i32 %add3, %add4
+  %ret = add i32 %ret1, %ret2
+  ret i32 %ret
+}
+
+define i32 @f2(i32 %a, i32 %b) {
+bb:
+  %add1 = add i32 %a, %b
+  %add2 = add i32 %a, %b
+  %ret = add i32 %add1, %add2
+  ret i32 %ret
+}