From 5c89080469d28442a375c76b9b14331cf841f6a8 Mon Sep 17 00:00:00 2001
From: Ilia Filippov <ili.filippov@gmail.com>
Date: Fri, 14 Jun 2013 16:38:54 +0400
Subject: [PATCH] changes in function LLVMFlattenInsertChain

---
 llvmutil.cpp | 17 ++++++++++-------
 llvmutil.h   |  7 +++----
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/llvmutil.cpp b/llvmutil.cpp
index 1f157399..ebb60f40 100644
--- a/llvmutil.cpp
+++ b/llvmutil.cpp
@@ -600,9 +600,9 @@ lGetIntValue(llvm::Value *offset) {
 }
 
 
-llvm::Value * 
+llvm::Value *
 LLVMFlattenInsertChain(llvm::Value *inst, int vectorWidth,
-                        bool compare, bool undef) {
+                       bool compare, bool undef) {
     llvm::Value ** elements = new llvm::Value*[vectorWidth];
     for (int i = 0; i < vectorWidth; ++i) {
         elements[i] = NULL;
@@ -631,7 +631,7 @@ LLVMFlattenInsertChain(llvm::Value *inst, int vectorWidth,
             if (llvm::isa<llvm::UndefValue>(insertBase)) {
                 break;
             }
-    
+
             if (llvm::isa<llvm::ConstantVector>(insertBase) ||
                 llvm::isa<llvm::ConstantAggregateZero>(insertBase)) {
                 llvm::Constant *cv = llvm::dyn_cast<llvm::Constant>(insertBase);
@@ -648,17 +648,20 @@ LLVMFlattenInsertChain(llvm::Value *inst, int vectorWidth,
                 // They are not equal to each other so we should return NULL if compare
                 // and first element if we have it.
                 Assert(compare == true ||  elements[0] != NULL);
-                if (compare)
+                if (compare) {
                     return NULL;
-                else
+                }
+                else {
                     return elements[0];
+                }
             }
             // TODO: Also, should we handle some other values like
             // ConstantDataVectors.
         }
-        if (compare == false)
-            //We simply want first element 
+        if (compare == false) {
+            //We simply want first element
             return elements[0];
+        }
 
         int null_number = 0;
         int NonNull = 0;
diff --git a/llvmutil.h b/llvmutil.h
index 95437c3f..d6c5ede0 100644
--- a/llvmutil.h
+++ b/llvmutil.h
@@ -270,10 +270,9 @@ extern bool LLVMExtractVectorInts(llvm::Value *v, int64_t ret[], int *nElts);
        %broadcast.1 = shufflevector <4 x i32> %smear.0, <4 x i32> undef,
                                                   <4 x i32> zeroinitializer
     Function returns:
-    First element of array if compare is false,
-    NonNull element only if all elements are equal or NULL if compare is true,
-    NonNull element only if all elements are equal if compare is true and undef is false,
-    NULL if all elements are NULLs
+    Compare all elements and return one of them if all are equal, otherwise NULL.
+    If compare argument is false, don't do compare and return first element instead.
+    If undef argument is true, ignore undef elements (but all undef yields NULL anyway).
  */
 extern llvm::Value * LLVMFlattenInsertChain (llvm::Value *inst, int vectorWidth,
     bool compare = true, bool undef = true);