Reimplement the parameter attributes support, phase #1. hilights:

1. There is now a "PAListPtr" class, which is a smart pointer around
   the underlying uniqued parameter attribute list object, and manages
   its refcount.  It is now impossible to mess up the refcount.
2. PAListPtr is now the main interface to the underlying object, and
   the underlying object is now completely opaque.
3. Implementation details like SmallVector and FoldingSet are now no
   longer part of the interface.
4. You can create a PAListPtr with an arbitrary sequence of
   ParamAttrsWithIndex's, no need to make a SmallVector of a specific 
   size (you can just use an array or scalar or vector if you wish).
5. All the client code that had to check for a null pointer before
   dereferencing the pointer is simplified to just access the 
   PAListPtr directly.
6. The interfaces for adding attrs to a list and removing them is a
   bit simpler.

Phase #2 will rename some stuff (e.g. PAListPtr) and do other less 
invasive changes.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48289 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 17 deletions

diff --git a/lib/Transforms/IPO/ArgumentPromotion.cpp b/lib/Transforms/IPO/ArgumentPromotion.cpp
index 25fa0a292b..d7f122b564 100644
--- a/lib/Transforms/IPO/ArgumentPromotion.cpp
+++ b/lib/Transforms/IPO/ArgumentPromotion.cpp
@@ -35,7 +35,6 @@
 #include "llvm/Module.h"
 #include "llvm/CallGraphSCCPass.h"
 #include "llvm/Instructions.h"
-#include "llvm/ParamAttrsList.h"
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Analysis/CallGraph.h"
 #include "llvm/Target/TargetData.h"
@@ -401,11 +400,11 @@ Function *ArgPromotion::DoPromotion(Function *F,
   // ParamAttrs - Keep track of the parameter attributes for the arguments
   // that we are *not* promoting. For the ones that we do promote, the parameter
   // attributes are lost
-  ParamAttrsVector ParamAttrsVec;
-  const ParamAttrsList *PAL = F->getParamAttrs();
+  SmallVector<ParamAttrsWithIndex, 8> ParamAttrsVec;
+  const PAListPtr &PAL = F->getParamAttrs();
 
   // Add any return attributes.
-  if (ParameterAttributes attrs = PAL ? PAL->getParamAttrs(0) : ParamAttr::None)
+  if (ParameterAttributes attrs = PAL.getParamAttrs(0))
     ParamAttrsVec.push_back(ParamAttrsWithIndex::get(0, attrs));
 
   unsigned ArgIndex = 1;
@@ -420,8 +419,7 @@ Function *ArgPromotion::DoPromotion(Function *F,
       ++NumByValArgsPromoted;
     } else if (!ArgsToPromote.count(I)) {
       Params.push_back(I->getType());
-      if (ParameterAttributes attrs = PAL ? PAL->getParamAttrs(ArgIndex) : 
-                                            ParamAttr::None)
+      if (ParameterAttributes attrs = PAL.getParamAttrs(ArgIndex))
         ParamAttrsVec.push_back(ParamAttrsWithIndex::get(Params.size(), attrs));
     } else if (I->use_empty()) {
       ++NumArgumentsDead;
@@ -476,8 +474,8 @@ Function *ArgPromotion::DoPromotion(Function *F,
 
   // Recompute the parameter attributes list based on the new arguments for
   // the function.
-  NF->setParamAttrs(ParamAttrsList::get(ParamAttrsVec));
-  ParamAttrsVec.clear(); PAL = 0;
+  NF->setParamAttrs(PAListPtr::get(ParamAttrsVec.begin(), ParamAttrsVec.end()));
+  ParamAttrsVec.clear();
   
   if (F->hasCollector())
     NF->setCollector(F->getCollector());
@@ -494,11 +492,10 @@ Function *ArgPromotion::DoPromotion(Function *F,
   while (!F->use_empty()) {
     CallSite CS = CallSite::get(F->use_back());
     Instruction *Call = CS.getInstruction();
-    PAL = CS.getParamAttrs();
+    const PAListPtr &CallPAL = CS.getParamAttrs();
     
     // Add any return attributes.
-    if (ParameterAttributes attrs = PAL ? PAL->getParamAttrs(0) : 
-                                          ParamAttr::None)
+    if (ParameterAttributes attrs = CallPAL.getParamAttrs(0))
       ParamAttrsVec.push_back(ParamAttrsWithIndex::get(0, attrs));
 
     // Loop over the operands, inserting GEP and loads in the caller as
@@ -510,8 +507,7 @@ Function *ArgPromotion::DoPromotion(Function *F,
       if (!ArgsToPromote.count(I) && !ByValArgsToTransform.count(I)) {
         Args.push_back(*AI);          // Unmodified argument
         
-        if (ParameterAttributes Attrs = PAL ? PAL->getParamAttrs(ArgIndex) :
-                                              ParamAttr::None)
+        if (ParameterAttributes Attrs = CallPAL.getParamAttrs(ArgIndex))
           ParamAttrsVec.push_back(ParamAttrsWithIndex::get(Args.size(), Attrs));
         
       } else if (ByValArgsToTransform.count(I)) {
@@ -550,8 +546,7 @@ Function *ArgPromotion::DoPromotion(Function *F,
     // Push any varargs arguments on the list
     for (; AI != CS.arg_end(); ++AI, ++ArgIndex) {
       Args.push_back(*AI);
-      if (ParameterAttributes Attrs = PAL ? PAL->getParamAttrs(ArgIndex) :
-                                            ParamAttr::None)
+      if (ParameterAttributes Attrs = CallPAL.getParamAttrs(ArgIndex))
         ParamAttrsVec.push_back(ParamAttrsWithIndex::get(Args.size(), Attrs));
     }
 
@@ -560,11 +555,13 @@ Function *ArgPromotion::DoPromotion(Function *F,
       New = new InvokeInst(NF, II->getNormalDest(), II->getUnwindDest(),
                            Args.begin(), Args.end(), "", Call);
       cast<InvokeInst>(New)->setCallingConv(CS.getCallingConv());
-      cast<InvokeInst>(New)->setParamAttrs(ParamAttrsList::get(ParamAttrsVec));
+      cast<InvokeInst>(New)->setParamAttrs(PAListPtr::get(ParamAttrsVec.begin(),
+                                                          ParamAttrsVec.end()));
     } else {
       New = new CallInst(NF, Args.begin(), Args.end(), "", Call);
       cast<CallInst>(New)->setCallingConv(CS.getCallingConv());
-      cast<CallInst>(New)->setParamAttrs(ParamAttrsList::get(ParamAttrsVec));
+      cast<CallInst>(New)->setParamAttrs(PAListPtr::get(ParamAttrsVec.begin(),
+                                                        ParamAttrsVec.end()));
       if (cast<CallInst>(Call)->isTailCall())
         cast<CallInst>(New)->setTailCall();
     }