Fix PR5329: pay attention to constructor/destructor priority

when outputting them.  With this, the entire LLVM testsuite
passes when built with dragonegg.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138724 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 57 insertions, 13 deletions

diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 42d042e230..12c5684a9e 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1228,22 +1228,45 @@ void AsmPrinter::EmitLLVMUsedList(const Constant *List) {
   }
 }
 
-/// EmitXXStructorList - Emit the ctor or dtor list.  This just prints out the
-/// function pointers, ignoring the init priority.
+typedef std::pair<int, Constant*> Structor;
+
+static bool priority_order(const Structor& lhs, const Structor& rhs)
+{
+  return lhs.first < rhs.first;
+}
+
+/// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
+/// priority.
 void AsmPrinter::EmitXXStructorList(const Constant *List) {
   // Should be an array of '{ int, void ()* }' structs.  The first value is the
-  // init priority, which we ignore.
+  // init priority.
   if (!isa<ConstantArray>(List)) return;
-  const ConstantArray *InitList = cast<ConstantArray>(List);
-  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
-    if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
-      if (CS->getNumOperands() != 2) return;  // Not array of 2-element structs.
-
-      if (CS->getOperand(1)->isNullValue())
-        return;  // Found a null terminator, exit printing.
-      // Emit the function pointer.
-      EmitGlobalConstant(CS->getOperand(1));
-    }
+
+  // Sanity check the structors list.
+  const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
+  if (!InitList) return; // Not an array!
+  StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
+  if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
+  if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
+      !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
+
+  // Gather the structors in a form that's convenient for sorting by priority.
+  SmallVector<Structor, 8> Structors;
+  for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
+    ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
+    if (!CS) continue; // Malformed.
+    if (CS->getOperand(1)->isNullValue())
+      break;  // Found a null terminator, skip the rest.
+    ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
+    if (!Priority) continue; // Malformed.
+    Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
+                                       CS->getOperand(1)));
+  }
+
+  // Emit the function pointers in reverse priority order.
+  std::sort(Structors.rbegin(), Structors.rend(), priority_order);
+  for (unsigned i = 0, e = Structors.size(); i != e; ++i)
+    EmitGlobalConstant(Structors[i].second);
 }
 
 //===--------------------------------------------------------------------===//
diff --git a/test/CodeGen/X86/2011-08-29-InitOrder.ll b/test/CodeGen/X86/2011-08-29-InitOrder.ll
new file mode 100644
index 0000000000..4bec03c85c
--- /dev/null
+++ b/test/CodeGen/X86/2011-08-29-InitOrder.ll
@@ -0,0 +1,21 @@
+; RUN: llc < %s -mtriple=i386-linux-gnu | FileCheck %s
+; PR5329
+
+@llvm.global_ctors = appending global [3 x { i32, void ()* }] [{ i32, void ()* } { i32 2000, void ()* @construct_2 }, { i32, void ()* } { i32 3000, void ()* @construct_3 }, { i32, void ()* } { i32 1000, void ()* @construct_1 }]
+; CHECK: ctors
+; CHECK: construct_3
+; CHECK: construct_2
+; CHECK: construct_1
+
+@llvm.global_dtors = appending global [3 x { i32, void ()* }] [{ i32, void ()* } { i32 2000, void ()* @destruct_2 }, { i32, void ()* } { i32 1000, void ()* @destruct_1 }, { i32, void ()* } { i32 3000, void ()* @destruct_3 }]
+; CHECK: dtors
+; CHECK: destruct_3
+; CHECK: destruct_2
+; CHECK: destruct_1
+
+declare void @construct_1()
+declare void @construct_2()
+declare void @construct_3()
+declare void @destruct_1()
+declare void @destruct_2()
+declare void @destruct_3()