C++/C#: Move overrides of IRType::getByteSize() into leaf classes

Dave Bartolomeo · Dave Bartolomeo · commit 8e977dc6bf8d · 2020-06-16T16:48:42.000-04:00
See github#2272. I've added code comments in all of the places that future me will be tempted to hoist these overrides.
diff --git a/cpp/ql/src/semmle/code/cpp/ir/implementation/IRType.qll b/cpp/ql/src/semmle/code/cpp/ir/implementation/IRType.qll
@@ -111,6 +111,8 @@ private class IRSizedType extends IRType {
     this = TIRFunctionAddressType(byteSize) or
     this = TIROpaqueType(_, byteSize)
   }
+  // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
+  // overridden only in the leaf classes.
 }
 
 /**
@@ -137,6 +139,8 @@ class IRNumericType extends IRSizedType {
     this = TIRUnsignedIntegerType(byteSize) or
     this = TIRFloatingPointType(byteSize, _, _)
   }
+  // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
+  // overridden only in the leaf classes.
 }
 
 /**
@@ -147,9 +151,8 @@ class IRIntegerType extends IRNumericType {
     this = TIRSignedIntegerType(byteSize) or
     this = TIRUnsignedIntegerType(byteSize)
   }
-
-  pragma[noinline]
-  final override int getByteSize() { result = byteSize }
+  // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
+  // overridden only in the leaf classes.
 }
 
 /**
@@ -162,6 +165,9 @@ class IRSignedIntegerType extends IRIntegerType, TIRSignedIntegerType {
   final override Language::LanguageType getCanonicalLanguageType() {
     result = Language::getCanonicalSignedIntegerType(byteSize)
   }
+
+  pragma[noinline]
+  final override int getByteSize() { result = byteSize }
 }
 
 /**
@@ -174,6 +180,9 @@ class IRUnsignedIntegerType extends IRIntegerType, TIRUnsignedIntegerType {
   final override Language::LanguageType getCanonicalLanguageType() {
     result = Language::getCanonicalUnsignedIntegerType(byteSize)
   }
+
+  pragma[noinline]
+  final override int getByteSize() { result = byteSize }
 }
 
 /**
diff --git a/csharp/ql/src/experimental/ir/implementation/IRType.qll b/csharp/ql/src/experimental/ir/implementation/IRType.qll
@@ -111,6 +111,8 @@ private class IRSizedType extends IRType {
     this = TIRFunctionAddressType(byteSize) or
     this = TIROpaqueType(_, byteSize)
   }
+  // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
+  // overridden only in the leaf classes.
 }
 
 /**
@@ -137,6 +139,8 @@ class IRNumericType extends IRSizedType {
     this = TIRUnsignedIntegerType(byteSize) or
     this = TIRFloatingPointType(byteSize, _, _)
   }
+  // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
+  // overridden only in the leaf classes.
 }
 
 /**
@@ -147,9 +151,8 @@ class IRIntegerType extends IRNumericType {
     this = TIRSignedIntegerType(byteSize) or
     this = TIRUnsignedIntegerType(byteSize)
   }
-
-  pragma[noinline]
-  final override int getByteSize() { result = byteSize }
+  // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
+  // overridden only in the leaf classes.
 }
 
 /**
@@ -162,6 +165,9 @@ class IRSignedIntegerType extends IRIntegerType, TIRSignedIntegerType {
   final override Language::LanguageType getCanonicalLanguageType() {
     result = Language::getCanonicalSignedIntegerType(byteSize)
   }
+
+  pragma[noinline]
+  final override int getByteSize() { result = byteSize }
 }
 
 /**
@@ -174,6 +180,9 @@ class IRUnsignedIntegerType extends IRIntegerType, TIRUnsignedIntegerType {
   final override Language::LanguageType getCanonicalLanguageType() {
     result = Language::getCanonicalUnsignedIntegerType(byteSize)
   }
+
+  pragma[noinline]
+  final override int getByteSize() { result = byteSize }
 }
 
 /**

Original file line number	Diff line number	Diff line change
`@@ -111,6 +111,8 @@ private class IRSizedType extends IRType {`
`111`	`111`	`this = TIRFunctionAddressType(byteSize) or`
`112`	`112`	`this = TIROpaqueType(_, byteSize)`
`113`	`113`	`}`
	`114`	+ // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
	`115`	`+ // overridden only in the leaf classes.`
`114`	`116`	`}`
`115`	`117`
`116`	`118`	`/**`
`@@ -137,6 +139,8 @@ class IRNumericType extends IRSizedType {`
`137`	`139`	`this = TIRUnsignedIntegerType(byteSize) or`
`138`	`140`	`this = TIRFloatingPointType(byteSize, _, _)`
`139`	`141`	`}`
	`142`	+ // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
	`143`	`+ // overridden only in the leaf classes.`
`140`	`144`	`}`
`141`	`145`
`142`	`146`	`/**`
`@@ -147,9 +151,8 @@ class IRIntegerType extends IRNumericType {`
`147`	`151`	`this = TIRSignedIntegerType(byteSize) or`
`148`	`152`	`this = TIRUnsignedIntegerType(byteSize)`
`149`	`153`	`}`
`150`		`-`
`151`		`- pragma[noinline]`
`152`		`- final override int getByteSize() { result = byteSize }`
	`154`	+ // Don't override `getByteSize()` here. The optimizer seems to generate better code when this is
	`155`	`+ // overridden only in the leaf classes.`
`153`	`156`	`}`
`154`	`157`
`155`	`158`	`/**`
`@@ -162,6 +165,9 @@ class IRSignedIntegerType extends IRIntegerType, TIRSignedIntegerType {`
`162`	`165`	`final override Language::LanguageType getCanonicalLanguageType() {`
`163`	`166`	`result = Language::getCanonicalSignedIntegerType(byteSize)`
`164`	`167`	`}`
	`168`	`+`
	`169`	`+ pragma[noinline]`
	`170`	`+ final override int getByteSize() { result = byteSize }`
`165`	`171`	`}`
`166`	`172`
`167`	`173`	`/**`
`@@ -174,6 +180,9 @@ class IRUnsignedIntegerType extends IRIntegerType, TIRUnsignedIntegerType {`
`174`	`180`	`final override Language::LanguageType getCanonicalLanguageType() {`
`175`	`181`	`result = Language::getCanonicalUnsignedIntegerType(byteSize)`
`176`	`182`	`}`
	`183`	`+`
	`184`	`+ pragma[noinline]`
	`185`	`+ final override int getByteSize() { result = byteSize }`
`177`	`186`	`}`
`178`	`187`
`179`	`188`	`/**`