Clean up SemanticCFG

Author: Dave Bartolomeo

java/ql/lib/semmle/code/java/semantic/SemanticCFG.qll

@@ -4,30 +4,12 @@
 
 private import java
 private import SemanticExpr
-private import SemanticExprSpecific
+private import SemanticCFGSpecific::SemanticCFGConfig as Specific
 
-private newtype TSemBasicBlock = MkSemBasicBlock(BasicBlock block)
+class SemBasicBlock extends Specific::BasicBlock {
+  final predicate bbDominates(SemBasicBlock otherBlock) { Specific::bbDominates(this, otherBlock) }
 
-class SemBasicBlock extends TSemBasicBlock {
-  BasicBlock block;
+  final predicate hasDominanceInformation() { Specific::hasDominanceInformation(this) }
 
-  SemBasicBlock() { this = MkSemBasicBlock(block) }
-
-  final string toString() { result = block.toString() }
-
-  final Location getLocation() { result = block.getLocation() }
-
-  final predicate bbDominates(SemBasicBlock otherBlock) {
-    block.bbDominates(getJavaBasicBlock(otherBlock))
-  }
-
-  final SemExpr getAnExpr() { SemanticExprConfig::getExprBasicBlock(result) = this }
-}
-
-SemBasicBlock getSemanticBasicBlock(BasicBlock block) { result = MkSemBasicBlock(block) }
-
-BasicBlock getJavaBasicBlock(SemBasicBlock block) { block = getSemanticBasicBlock(result) }
-
-predicate semHasDominanceInformation(SemBasicBlock bb) {
-  hasDominanceInformation(getJavaBasicBlock(bb))
+  final SemExpr getAnExpr() { result.getBasicBlock() = this }
 }

java/ql/lib/semmle/code/java/semantic/SemanticCFGSpecific.qll

@@ -0,0 +1,20 @@
+private import java as J
+private import SemanticCFG
+
+module SemanticCFGConfig {
+  class BasicBlock instanceof J::BasicBlock {
+    final string toString() { result = this.(J::BasicBlock).toString() }
+
+    final J::Location getLocation() { result = this.(J::BasicBlock).getLocation() }
+  }
+
+  predicate bbDominates(BasicBlock dominator, BasicBlock dominated) {
+    dominator.(J::BasicBlock).bbDominates(dominated.(J::BasicBlock))
+  }
+
+  predicate hasDominanceInformation(BasicBlock block) { J::hasDominanceInformation(block) }
+}
+
+SemBasicBlock getSemanticBasicBlock(J::BasicBlock block) { result = block }
+
+J::BasicBlock getJavaBasicBlock(SemBasicBlock block) { block = getSemanticBasicBlock(result) }

java/ql/lib/semmle/code/java/semantic/SemanticExprSpecific.qll

@@ -1,6 +1,7 @@
 private import java as J
 private import SemanticCFG
 private import SemanticExpr
+private import SemanticCFGSpecific
 private import SemanticSSA
 private import SemanticType
 private import semmle.code.java.dataflow.SSA as SSA

java/ql/lib/semmle/code/java/semantic/SemanticGuard.qll

@@ -6,6 +6,7 @@ private import java
 private import semmle.code.java.controlflow.Guards
 private import semmle.code.java.controlflow.internal.GuardsLogic
 private import SemanticCFG
+private import SemanticCFGSpecific
 private import SemanticExpr
 private import SemanticExprSpecific
 private import SemanticSSA

java/ql/lib/semmle/code/java/semantic/SemanticSSA.qll

@@ -9,6 +9,7 @@ private import SemanticExpr
 private import SemanticType
 private import semmle.code.java.dataflow.internal.rangeanalysis.SsaReadPositionCommon
 private import SemanticExprSpecific
+private import SemanticCFGSpecific
 
 private newtype TSemSsaVariable = MkSemSsaVariable(SSA::SsaVariable var)
 
@@ -118,6 +119,6 @@ predicate semBackEdge(SemSsaPhiNode phi, SemSsaVariable inp, SemSsaReadPositionP
   // Conservatively assume that every edge is a back edge if we don't have dominance information.
   (
     phi.getBasicBlock().bbDominates(edge.getOrigBlock()) or
-    not semHasDominanceInformation(edge.getOrigBlock())
+    not edge.getOrigBlock().hasDominanceInformation()
   )
 }

java/ql/test/library-tests/dataflow/sign-analysis/diff.ql

@@ -2,6 +2,7 @@ import java
 import semmle.code.java.dataflow.SignAnalysis
 import semmle.code.java.semantic.analysis.SignAnalysisCommon
 import semmle.code.java.semantic.SemanticCFG
+import semmle.code.java.semantic.SemanticCFGSpecific
 import semmle.code.java.semantic.SemanticExpr
 import semmle.code.java.semantic.SemanticExprSpecific
 import semmle.code.java.semantic.SemanticSSA