[analyzer] Add -analyzer-config option for function size the inliner considers as large

Add an option (-analyzer-config min-blocks-for-inline-large=14) to control the function
size the inliner considers as large, in relation to "max-times-inline-large". The option
defaults to the original hard coded behaviour, which I believe should be adjustable with
the other inlining settings.

The analyzer-config test has been modified so that the analyzer will reach the
getMinBlocksForInlineLarge() method and store the result in the ConfigTable, to ensure it
is dumped by the debug checker.

A patch by Sean Eveson!

Differential Revision: http://reviews.llvm.org/D12406

llvm-svn: 247463

clang/include/clang/StaticAnalyzer/Core/AnalyzerOptions.h

@@ -253,6 +253,9 @@ private:
   /// \sa getMaxTimesInlineLarge
   Optional<unsigned> MaxTimesInlineLarge;
 
+  /// \sa getMinCFGSizeTreatFunctionsAsLarge
+  Optional<unsigned> MinCFGSizeTreatFunctionsAsLarge;
+
   /// \sa getMaxNodesPerTopLevelFunction
   Optional<unsigned> MaxNodesPerTopLevelFunction;
 
@@ -505,6 +508,13 @@ public:
   /// This is controlled by the 'max-times-inline-large' config option.
   unsigned getMaxTimesInlineLarge();
 
+  /// Returns the number of basic blocks a function needs to have to be
+  /// considered large for the 'max-times-inline-large' config option.
+  ///
+  /// This is controlled by the 'min-cfg-size-treat-functions-as-large' config
+  /// option.
+  unsigned getMinCFGSizeTreatFunctionsAsLarge();
+
   /// Returns the maximum number of nodes the analyzer can generate while
   /// exploring a top level function (for each exploded graph).
   /// 150000 is default; 0 means no limit.

clang/lib/StaticAnalyzer/Core/AnalyzerOptions.cpp

@@ -295,6 +295,13 @@ unsigned AnalyzerOptions::getMaxTimesInlineLarge() {
   return MaxTimesInlineLarge.getValue();
 }
 
+unsigned AnalyzerOptions::getMinCFGSizeTreatFunctionsAsLarge() {
+  if (!MinCFGSizeTreatFunctionsAsLarge.hasValue())
+    MinCFGSizeTreatFunctionsAsLarge = getOptionAsInteger(
+      "min-cfg-size-treat-functions-as-large", 14);
+  return MinCFGSizeTreatFunctionsAsLarge.getValue();
+}
+
 unsigned AnalyzerOptions::getMaxNodesPerTopLevelFunction() {
   if (!MaxNodesPerTopLevelFunction.hasValue()) {
     int DefaultValue = 0;

clang/lib/StaticAnalyzer/Core/ExprEngineCallAndReturn.cpp

@@ -870,7 +870,8 @@ bool ExprEngine::shouldInlineCall(const CallEvent &Call, const Decl *D,
   // Do not inline large functions too many times.
   if ((Engine.FunctionSummaries->getNumTimesInlined(D) >
        Opts.getMaxTimesInlineLarge()) &&
-      CalleeCFG->getNumBlockIDs() > 13) {
+       CalleeCFG->getNumBlockIDs() >=
+       Opts.getMinCFGSizeTreatFunctionsAsLarge()) {
     NumReachedInlineCountMax++;
     return false;
   }

clang/test/Analysis/analyzer-config.c

@@ -1,22 +1,30 @@
-// RUN: %clang -target x86_64-apple-darwin10 --analyze %s -o /dev/null -Xclang -analyzer-checker=debug.ConfigDumper > %t 2>&1
+// RUN: %clang -target x86_64-apple-darwin10 --analyze %s -o /dev/null -Xclang -analyzer-checker=debug.ConfigDumper -Xclang -analyzer-max-loop -Xclang 34 > %t 2>&1
 // RUN: FileCheck --input-file=%t %s
 
 void bar() {}
-void foo() { bar(); }
+void foo() {
+  // Call bar 33 times so max-times-inline-large is met and
+  // min-blocks-for-inline-large is checked
+  for (int i = 0; i < 34; ++i) {
+    bar();
+  }
+}
 
 // CHECK: [config]
 // CHECK-NEXT: cfg-conditional-static-initializers = true
 // CHECK-NEXT: cfg-temporary-dtors = false
 // CHECK-NEXT: faux-bodies = true
 // CHECK-NEXT: graph-trim-interval = 1000
+// CHECK-NEXT: inline-lambdas = true
 // CHECK-NEXT: ipa = dynamic-bifurcate
 // CHECK-NEXT: ipa-always-inline-size = 3
 // CHECK-NEXT: leak-diagnostics-reference-allocation = false
 // CHECK-NEXT: max-inlinable-size = 50
 // CHECK-NEXT: max-nodes = 150000
 // CHECK-NEXT: max-times-inline-large = 32
+// CHECK-NEXT: min-cfg-size-treat-functions-as-large = 14
 // CHECK-NEXT: mode = deep
 // CHECK-NEXT: region-store-small-struct-limit = 2
 // CHECK-NEXT: [stats]
-// CHECK-NEXT: num-entries = 12
+// CHECK-NEXT: num-entries = 14
 

clang/test/Analysis/analyzer-config.cpp

@@ -1,8 +1,14 @@
-// RUN: %clang -target x86_64-apple-darwin10 --analyze %s -o /dev/null -Xclang -analyzer-checker=debug.ConfigDumper > %t 2>&1
+// RUN: %clang -target x86_64-apple-darwin10 --analyze %s -o /dev/null -Xclang -analyzer-checker=debug.ConfigDumper -Xclang -analyzer-max-loop -Xclang 34 > %t 2>&1
 // RUN: FileCheck --input-file=%t %s
 
 void bar() {}
-void foo() { bar(); }
+void foo() {
+  // Call bar 33 times so max-times-inline-large is met and
+  // min-blocks-for-inline-large is checked
+  for (int i = 0; i < 34; ++i) {
+    bar();
+  }
+}
 
 class Foo {
 public:
@@ -20,13 +26,15 @@ public:
 // CHECK-NEXT: cfg-temporary-dtors = false
 // CHECK-NEXT: faux-bodies = true
 // CHECK-NEXT: graph-trim-interval = 1000
+// CHECK-NEXT: inline-lambdas = true
 // CHECK-NEXT: ipa = dynamic-bifurcate
 // CHECK-NEXT: ipa-always-inline-size = 3
 // CHECK-NEXT: leak-diagnostics-reference-allocation = false
 // CHECK-NEXT: max-inlinable-size = 50
 // CHECK-NEXT: max-nodes = 150000
 // CHECK-NEXT: max-times-inline-large = 32
+// CHECK-NEXT: min-cfg-size-treat-functions-as-large = 14
 // CHECK-NEXT: mode = deep
 // CHECK-NEXT: region-store-small-struct-limit = 2
 // CHECK-NEXT: [stats]
-// CHECK-NEXT: num-entries = 17
+// CHECK-NEXT: num-entries = 19