objective-c blocks: Consider padding due to alignment

after the fixed size block header when generating
captured block variable info. // rdar://12773256

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169285 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/AST/DeclPrinter.cpp b/lib/AST/DeclPrinter.cpp
index 35bff1035ecfadf45d9539680858c895f133bfde..493e46be47a040afa10e8ad403869cd19dbd62a9 100644 (file)
--- a/lib/AST/DeclPrinter.cpp
+++ b/lib/AST/DeclPrinter.cpp
@@ -970,6 +970,17 @@ void DeclPrinter::VisitObjCCategoryImplDecl(ObjCCategoryImplDecl *PID) {
 
 void DeclPrinter::VisitObjCCategoryDecl(ObjCCategoryDecl *PID) {
   Out << "@interface " << *PID->getClassInterface() << '(' << *PID << ")\n";
+  if (PID->ivar_size() > 0) {
+    Out << "{\n";
+    Indentation += Policy.Indentation;
+    for (ObjCCategoryDecl::ivar_iterator I = PID->ivar_begin(),
+         E = PID->ivar_end(); I != E; ++I) {
+      Indent() << I->getType().getAsString(Policy) << ' ' << **I << ";\n";
+    }
+    Indentation -= Policy.Indentation;
+    Out << "}\n";
+  }
+  
   VisitDeclContext(PID, false);
   Out << "@end";
 

diff --git a/lib/CodeGen/CGBlocks.cpp b/lib/CodeGen/CGBlocks.cpp
index 1d8b326d2074964a3f9398896849fde9ab229b05..d181da2de662a6104f7d13c5038c59c2d7e9d28a 100644 (file)
--- a/lib/CodeGen/CGBlocks.cpp
+++ b/lib/CodeGen/CGBlocks.cpp
@@ -428,7 +428,11 @@ static void computeBlockInfo(CodeGenModule &CGM, CodeGenFunction *CGF,
   // to get reproducible results.  There should probably be an
   // llvm::array_pod_stable_sort.
   std::stable_sort(layout.begin(), layout.end());
-
+  
+  // Needed for blocks layout info.
+  info.BlockHeaderForcedGapOffset = info.BlockSize;
+  info.BlockHeaderForcedGapSize = CharUnits::Zero();
+  
   CharUnits &blockSize = info.BlockSize;
   info.BlockAlign = std::max(maxFieldAlign, info.BlockAlign);
 
@@ -469,17 +473,22 @@ static void computeBlockInfo(CodeGenModule &CGM, CodeGenFunction *CGF,
         endAlign = getLowBit(blockSize);
 
         // ...until we get to the alignment of the maximum field.
-        if (endAlign >= maxFieldAlign)
+        if (endAlign >= maxFieldAlign) {
+          if (li == first) {
+            // No user field was appended. So, a gap was added.
+            // Save total gap size for use in block layout bit map.
+            info.BlockHeaderForcedGapSize = li->Size;
+          }
           break;
+        }
       }
-
       // Don't re-append everything we just appended.
       layout.erase(first, li);
     }
   }
 
   assert(endAlign == getLowBit(blockSize));
-
+  
   // At this point, we just have to add padding if the end align still
   // isn't aligned right.
   if (endAlign < maxFieldAlign) {
@@ -494,7 +503,6 @@ static void computeBlockInfo(CodeGenModule &CGM, CodeGenFunction *CGF,
 
   assert(endAlign >= maxFieldAlign);
   assert(endAlign == getLowBit(blockSize));
-
   // Slam everything else on now.  This works because they have
   // strictly decreasing alignment and we expect that size is always a
   // multiple of alignment.

diff --git a/lib/CodeGen/CGBlocks.h b/lib/CodeGen/CGBlocks.h
index e63d4b6b1f0386456335c47bfff2131d21484e8d..0e40478fad7371586dee40bde9a96606881327a3 100644 (file)
--- a/lib/CodeGen/CGBlocks.h
+++ b/lib/CodeGen/CGBlocks.h
@@ -211,6 +211,14 @@ public:
   const BlockExpr *BlockExpression;
   CharUnits BlockSize;
   CharUnits BlockAlign;
+  
+  // Offset of the gap caused by block header having a smaller
+  // alignment than the alignment of the block descriptor. This
+  // is the gap offset before the first capturued field.
+  CharUnits BlockHeaderForcedGapOffset;
+  // Gap size caused by aligning first field after block header.
+  // This could be zero if no forced alignment is required.
+  CharUnits BlockHeaderForcedGapSize;
 
   /// An instruction which dominates the full-expression that the
   /// block is inside.

diff --git a/lib/CodeGen/CGObjCMac.cpp b/lib/CodeGen/CGObjCMac.cpp
index f4b42bb9b7dc66bcd454e50d24b26a30c444be7b..d84875bfd5145ac7fbd7f421808b4c8417d278ad 100644 (file)
--- a/lib/CodeGen/CGObjCMac.cpp
+++ b/lib/CodeGen/CGObjCMac.cpp
@@ -2424,7 +2424,10 @@ llvm::Constant *CGObjCCommonMac::BuildRCBlockLayout(CodeGenModule &CGM,
   
   // Ignore the optional 'this' capture: C++ objects are not assumed
   // to be GC'ed.
-  
+  if (blockInfo.BlockHeaderForcedGapSize != CharUnits::Zero())
+    UpdateRunSkipBlockVars(false, Qualifiers::OCL_None,
+                           blockInfo.BlockHeaderForcedGapOffset,
+                           blockInfo.BlockHeaderForcedGapSize);
   // Walk the captured variables.
   for (BlockDecl::capture_const_iterator ci = blockDecl->capture_begin(),
        ce = blockDecl->capture_end(); ci != ce; ++ci) {

diff --git a/test/CodeGenObjC/arc-captured-32bit-block-var-layout-2.m b/test/CodeGenObjC/arc-captured-32bit-block-var-layout-2.m
new file mode 100644 (file)
index 0000000..909d413
--- /dev/null
+++ b/test/CodeGenObjC/arc-captured-32bit-block-var-layout-2.m
@@ -0,0 +1,60 @@
+// RUN: %clang_cc1 -fblocks -fobjc-arc -fobjc-runtime-has-weak -triple i386-apple-darwin -O0 -emit-llvm %s -o %t-64.s
+// RUN: FileCheck --input-file=%t-64.s %s
+// rdar://12773256
+
+@class NSString;
+extern void NSLog(NSString *format, ...);
+extern int printf(const char *, ...);
+
+int main() {
+  NSString *strong;
+  unsigned long long eightByte = 0x8001800181818181ull;
+  // Test1
+// CHECK: @"\01L_OBJC_CLASS_NAME_{{.*}}" = internal global [3 x i8] c"\220\00"
+  void (^block1)() = ^{ printf("%#llx", eightByte); NSLog(@"%@", strong); };
+// %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, %0*, i64, %0* }>, align 8
+// block variable layout: BL_NON_OBJECT_WORD:3, BL_STRONG:1, BL_OPERATOR:0
+
+  // Test2
+  int i = 1;
+// CHECK: @"\01L_OBJC_CLASS_NAME_{{.*}}" = internal global [3 x i8] c"#0\00"
+  void (^block2)() = ^{ printf("%#llx, %d", eightByte, i); NSLog(@"%@", strong); };
+// %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i32, i64, i32, %0* }>, align 8
+// block variable layout: BL_NON_OBJECT_WORD:4, BL_STRONG:1, BL_OPERATOR:0
+
+  //  Test3
+  char ch = 'a';
+// CHECK: @"\01L_OBJC_CLASS_NAME_{{.*}}" = internal global [3 x i8] c"\220\00"
+  void (^block3)() = ^{ printf("%c %#llx", ch, eightByte); NSLog(@"%@", strong); };
+// %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, %0*, i64, %0*, i8 }>, align 8
+// block variable layout: BL_NON_OBJECT_WORD:3, BL_STRONG:1, BL_OPERATOR:0  
+
+  // Test4
+  unsigned long fourByte = 0x8001ul;
+// CHECK: @"\01L_OBJC_CLASS_NAME_{{.*}}" = internal global [3 x i8] c" 0\00"
+  void (^block4)() = ^{ printf("%c %#lx", ch, fourByte); NSLog(@"%@", strong); };
+// block variable layout: BL_NON_OBJECT_WORD:1, BL_STRONG:1, BL_OPERATOR:0
+// %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, i32, %0*, i8 }>, align 4
+
+  // Test5
+// CHECK: @"\01L_OBJC_CLASS_NAME_{{.*}}" = internal global [3 x i8] c"\220\00"
+  void (^block5)() = ^{ NSLog(@"%@", strong); printf("%c %#llx", ch, eightByte); };
+// %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, %0*, i64, %0*, i8 }>, align 8
+// block variable layout: BL_NON_OBJECT_WORD:3, BL_STRONG:1, BL_OPERATOR:0
+
+  // Test6
+// CHECK: @"\01L_OBJC_CLASS_NAME_{{.*}}" = internal global [1 x i8] zeroinitializer
+  void (^block6)() = ^{ printf("%#llx", eightByte); };
+// %block = alloca <{ i8*, i32, i32, i8*, %struct.__block_descriptor*, [4 x i8], i64 }>, align 8
+// block variable layout: BL_OPERATOR:0
+}
+
+/**
+struct __block_literal_generic { // 32bytes (64bit) and 20 bytes (32bit).
+0  void *__isa;
+4  int __flags;
+8  int __reserved;
+12  void (*__invoke)(void *);
+16  struct __block_descriptor *__descriptor;
+};
+*/