[llvm-commits] [llvm] r142684 - in /llvm/trunk: lib/Transforms/Utils/CloneFunction.cpp test/Transforms/Inline/blockaddress.ll

[Eli Friedman]

Author: efriedma
Date: Fri Oct 21 15:45:19 2011
New Revision: 142684

URL: http://llvm.org/viewvc/llvm-project?rev=142684&view=rev
Log:
Remap blockaddress correctly when inlining a function. Fixes PR10162.


Added:
    llvm/trunk/test/Transforms/Inline/blockaddress.ll
Modified:
    llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp

Modified: llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp?rev=142684&r1=142683&r2=142684&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/CloneFunction.cpp Fri Oct 21 15:45:19 2011
@@ -113,8 +113,23 @@
 
     // Create a new basic block and copy instructions into it!
     BasicBlock *CBB = CloneBasicBlock(&BB, VMap, NameSuffix, NewFunc, CodeInfo);
-    VMap[&BB] = CBB;                       // Add basic block mapping.
 
+    // Add basic block mapping.
+    VMap[&BB] = CBB;
+
+    // It is only legal to clone a function if a block address within that
+    // function is never referenced outside of the function.  Given that, we
+    // want to map block addresses from the old function to block addresses in
+    // the clone. (This is different from the generic ValueMapper
+    // implementation, which generates an invalid blockaddress when
+    // cloning a function.)
+    if (BB.hasAddressTaken()) {
+      Constant *OldBBAddr = BlockAddress::get(const_cast<Function*>(OldFunc),
+                                              const_cast<BasicBlock*>(&BB));
+      VMap[OldBBAddr] = BlockAddress::get(NewFunc, CBB);                                         
+    }
+
+    // Note return instructions for the caller.
     if (ReturnInst *RI = dyn_cast<ReturnInst>(CBB->getTerminator()))
       Returns.push_back(RI);
   }
@@ -224,6 +239,22 @@
   BBEntry = NewBB = BasicBlock::Create(BB->getContext());
   if (BB->hasName()) NewBB->setName(BB->getName()+NameSuffix);
 
+  // It is only legal to clone a function if a block address within that
+  // function is never referenced outside of the function.  Given that, we
+  // want to map block addresses from the old function to block addresses in
+  // the clone. (This is different from the generic ValueMapper
+  // implementation, which generates an invalid blockaddress when
+  // cloning a function.)
+  //
+  // Note that we don't need to fix the mapping for unreachable blocks;
+  // the default mapping there is safe.
+  if (BB->hasAddressTaken()) {
+    Constant *OldBBAddr = BlockAddress::get(const_cast<Function*>(OldFunc),
+                                            const_cast<BasicBlock*>(BB));
+    VMap[OldBBAddr] = BlockAddress::get(NewFunc, NewBB);
+  }
+    
+
   bool hasCalls = false, hasDynamicAllocas = false, hasStaticAllocas = false;
   
   // Loop over all instructions, and copy them over, DCE'ing as we go.  This

Added: llvm/trunk/test/Transforms/Inline/blockaddress.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/Inline/blockaddress.ll?rev=142684&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/Inline/blockaddress.ll (added)
+++ llvm/trunk/test/Transforms/Inline/blockaddress.ll Fri Oct 21 15:45:19 2011
@@ -0,0 +1,27 @@
+; RUN: opt -inline -S < %s | FileCheck %s
+; PR10162
+
+; Make sure the blockaddress is mapped correctly when doit is inlined
+; CHECK: store i8* blockaddress(@f, %here.i), i8** @ptr1, align 8
+
+ at i = global i32 1, align 4
+ at ptr1 = common global i8* null, align 8
+
+define void @doit(i8** nocapture %pptr, i32 %cond) nounwind uwtable {
+entry:
+  %tobool = icmp eq i32 %cond, 0
+  br i1 %tobool, label %if.end, label %here
+
+here:
+  store i8* blockaddress(@doit, %here), i8** %pptr, align 8
+  br label %if.end
+
+if.end:
+  ret void
+}
+
+define void @f(i32 %cond) nounwind uwtable {
+entry:
+  call void @doit(i8** @ptr1, i32 %cond)
+  ret void
+}