[MemProf] Disable cloning of callsites in recursive cycles by default

llvm/lib/Transforms/IPO/MemProfContextDisambiguation.cpp

@@ -122,9 +122,9 @@ static cl::opt<unsigned>
                         cl::desc("Max depth to recursively search for missing "
                                  "frames through tail calls."));
 
-// By default enable cloning of callsites involved with recursive cycles
+// Optionally enable cloning of callsites involved with recursive cycles
 static cl::opt<bool> AllowRecursiveCallsites(
-    "memprof-allow-recursive-callsites", cl::init(true), cl::Hidden,
+    "memprof-allow-recursive-callsites", cl::init(false), cl::Hidden,
     cl::desc("Allow cloning of callsites involved in recursive cycles"));
 
 // When disabled, try to detect and prevent cloning of recursive contexts.

llvm/test/ThinLTO/X86/memprof-recursive.ll

@@ -5,7 +5,7 @@
 
 ; RUN: opt -thinlto-bc %s >%t.o
 
-;; By default we should enable cloning of contexts involved with recursive
+;; Check behavior when we enable cloning of contexts involved with recursive
 ;; cycles, but not through the cycle itself. I.e. until full support for
 ;; recursion is added, the cloned recursive call from C back to B (line 12) will
 ;; not be updated to call a clone.
@@ -18,6 +18,7 @@
 ; RUN:  -r=%t.o,_Znam, \
 ; RUN:  -memprof-verify-ccg -memprof-verify-nodes \
 ; RUN:  -pass-remarks=memprof-context-disambiguation \
+; RUN:	-memprof-allow-recursive-callsites=true \
 ; RUN:  -o %t.out 2>&1 | FileCheck %s \
 ; RUN:  --implicit-check-not "memprof_recursive3.cc:12:10: call in clone _Z1Ci.memprof.1 assigned" \
 ; RUN:  --check-prefix=ALLOW-RECUR-CALLSITES --check-prefix=ALLOW-RECUR-CONTEXTS
@@ -38,6 +39,21 @@
 ; RUN:  --implicit-check-not="created clone" \
 ; RUN:	--implicit-check-not="marked with memprof allocation attribute cold"
 
+;; Check the default behavior (disabled recursive callsites).
+; RUN: llvm-lto2 run %t.o -enable-memprof-context-disambiguation \
+; RUN:  -supports-hot-cold-new \
+; RUN:  -r=%t.o,_Z1Dv,plx \
+; RUN:  -r=%t.o,_Z1Ci,plx \
+; RUN:  -r=%t.o,_Z1Bi,plx \
+; RUN:  -r=%t.o,main,plx \
+; RUN:  -r=%t.o,_Znam, \
+; RUN:  -memprof-verify-ccg -memprof-verify-nodes \
+; RUN:  -pass-remarks=memprof-context-disambiguation \
+; RUN:  -o %t.out 2>&1 | FileCheck %s --allow-empty \
+; RUN:  --implicit-check-not "memprof_recursive3.cc:12:10: call in clone _Z1Ci.memprof.1 assigned" \
+; RUN:  --implicit-check-not="created clone" \
+; RUN:	--implicit-check-not="marked with memprof allocation attribute cold"
+
 ;; Skipping recursive contexts should prevent spurious call to cloned version of
 ;; B from the context starting at memprof_recursive.cc:19:13, which is actually
 ;; recursive (until that support is added).
@@ -50,6 +66,7 @@
 ; RUN:  -r=%t.o,_Znam, \
 ; RUN:  -memprof-verify-ccg -memprof-verify-nodes \
 ; RUN:  -pass-remarks=memprof-context-disambiguation \
+; RUN:	-memprof-allow-recursive-callsites=true \
 ; RUN:	-memprof-allow-recursive-contexts=false \
 ; RUN:  -o %t.out 2>&1 | FileCheck %s \
 ; RUN:  --implicit-check-not "memprof_recursive3.cc:12:10: call in clone _Z1Ci.memprof.1 assigned" \

llvm/test/Transforms/MemProfContextDisambiguation/recursive.ll

@@ -34,13 +34,14 @@
 ;;
 ;; The IR was then reduced using llvm-reduce with the expected FileCheck input.
 
-;; By default we should enable cloning of contexts involved with recursive
+;; Check behavior when we enable cloning of contexts involved with recursive
 ;; cycles, but not through the cycle itself. I.e. until full support for
 ;; recursion is added, the cloned recursive call from C back to B (line 12) will
 ;; not be updated to call a clone.
 ; RUN: opt -passes=memprof-context-disambiguation -supports-hot-cold-new \
 ; RUN:  -memprof-verify-ccg -memprof-verify-nodes \
 ; RUN:  -pass-remarks=memprof-context-disambiguation \
+; RUN:	-memprof-allow-recursive-callsites=true \
 ; RUN:  %s -S 2>&1 | FileCheck %s \
 ; RUN:  --implicit-check-not "memprof_recursive3.cc:12:10: call in clone _Z1Ci.memprof.1 assigned" \
 ; RUN:  --check-prefix=ALL --check-prefix=ALLOW-RECUR-CALLSITES --check-prefix=ALLOW-RECUR-CONTEXTS
@@ -56,12 +57,23 @@
 ; RUN:	--implicit-check-not="marked with memprof allocation attribute cold" \
 ; RUN:  --check-prefix=ALL
 
+;; Check the default behavior (disabled recursive callsites).
+; RUN: opt -passes=memprof-context-disambiguation -supports-hot-cold-new \
+; RUN:  -memprof-verify-ccg -memprof-verify-nodes \
+; RUN:  -pass-remarks=memprof-context-disambiguation \
+; RUN:  %s -S 2>&1 | FileCheck %s \
+; RUN:  --implicit-check-not "memprof_recursive3.cc:12:10: call in clone _Z1Ci.memprof.1 assigned" \
+; RUN:  --implicit-check-not="created clone" \
+; RUN:	--implicit-check-not="marked with memprof allocation attribute cold" \
+; RUN:  --check-prefix=ALL
+
 ;; Skipping recursive contexts should prevent spurious call to cloned version of
 ;; B from the context starting at memprof_recursive.cc:19:13, which is actually
 ;; recursive (until that support is added).
 ; RUN: opt -passes=memprof-context-disambiguation -supports-hot-cold-new \
 ; RUN:  -memprof-verify-ccg -memprof-verify-nodes \
 ; RUN:  -pass-remarks=memprof-context-disambiguation \
+; RUN:	-memprof-allow-recursive-callsites=true \
 ; RUN:	-memprof-allow-recursive-contexts=false \
 ; RUN:  %s -S 2>&1 | FileCheck %s \
 ; RUN:  --implicit-check-not "memprof_recursive3.cc:12:10: call in clone _Z1Ci.memprof.1 assigned" \