+<p>Converting from the old EH API to the new EH API is rather simple, because a
+ lot of complexity has been removed. The two intrinsics,
+ <code>@llvm.eh.exception</code> and <code>@llvm.eh.selector</code> have been
+ superceded by the <code>landingpad</code> instruction. Instead of generating
+ a call to <code>@llvm.eh.exception</code> and <code>@llvm.eh.selector</code>:
+
+<div class="doc_code">
+<pre>
+Function *ExcIntr = Intrinsic::getDeclaration(TheModule,
+ Intrinsic::eh_exception);
+Function *SlctrIntr = Intrinsic::getDeclaration(TheModule,
+ Intrinsic::eh_selector);
+
+// The exception pointer.
+Value *ExnPtr = Builder.CreateCall(ExcIntr, "exc_ptr");
+
+std::vector<Value*> Args;
+Args.push_back(ExnPtr);
+Args.push_back(Builder.CreateBitCast(Personality,
+ Type::getInt8PtrTy(Context)));
+
+<i>// Add selector clauses to Args.</i>
+
+// The selector call.
+Builder.CreateCall(SlctrIntr, Args, "exc_sel");
+</pre>
+</div>
+
+<p>You should instead generate a <code>landingpad</code> instruction, that
+ returns an exception object and selector value:</p>
+
+<div class="doc_code">
+<pre>
+LandingPadInst *LPadInst =
+ Builder.CreateLandingPad(StructType::get(Int8PtrTy, Int32Ty, NULL),
+ Personality, 0);
+
+Value *LPadExn = Builder.CreateExtractValue(LPadInst, 0);
+Builder.CreateStore(LPadExn, getExceptionSlot());
+
+Value *LPadSel = Builder.CreateExtractValue(LPadInst, 1);
+Builder.CreateStore(LPadSel, getEHSelectorSlot());
+</pre>
+</div>
+
+<p>It's now trivial to add the individual clauses to the <code>landingpad</code>
+ instruction.</p>
+
+<div class="doc_code">
+<pre>
+<i><b>// Adding a catch clause</b></i>
+Constant *TypeInfo = getTypeInfo();
+LPadInst->addClause(TypeInfo);
+
+<i><b>// Adding a C++ catch-all</b></i>
+LPadInst->addClause(Constant::getNullValue(Builder.getInt8PtrTy()));
+
+<i><b>// Adding a cleanup</b></i>
+LPadInst->setCleanup(true);
+
+<i><b>// Adding a filter clause</b></i>
+std::vector<Constant*> TypeInfos;
+Constant *TypeInfo = getFilterTypeInfo();
+TypeInfos.push_back(Builder.CreateBitCast(TypeInfo, Builder.getInt8PtrTy()));
+
+ArrayType *FilterTy = ArrayType::get(Int8PtrTy, TypeInfos.size());
+LPadInst->addClause(ConstantArray::get(FilterTy, TypeInfos));
+</pre>
+</div>
+
+<p>Converting from using the <code>@llvm.eh.resume</code> intrinsic to
+ the <code>resume</code> instruction is trivial. It takes the exception
+ pointer and exception selector values returned by
+ the <code>landingpad</code> instruction:</p>
+
+<div class="doc_code">
+<pre>
+Type *UnwindDataTy = StructType::get(Builder.getInt8PtrTy(),
+ Builder.getInt32Ty(), NULL);
+Value *UnwindData = UndefValue::get(UnwindDataTy);
+Value *ExcPtr = Builder.CreateLoad(getExceptionObjSlot());
+Value *ExcSel = Builder.CreateLoad(getExceptionSelSlot());
+UnwindData = Builder.CreateInsertValue(UnwindData, ExcPtr, 0, "exc_ptr");
+UnwindData = Builder.CreateInsertValue(UnwindData, ExcSel, 1, "exc_sel");
+Builder.CreateResume(UnwindData);
+</pre>
+</div>
+
+</div>
+
+<!--=========================================================================-->
+<h3>
+<a name="loopoptimization">Loop Optimization Improvements</a>
+</h3>
+
+<div>
+<p>The induction variable simplification pass in 3.0 only modifies
+ induction variables when profitable. Sign and zero extension
+ elimination, linear function test replacement, loop unrolling, and
+ other simplifications that require induction variable analysis have
+ been generalized so they no longer require loops to be rewritten in a
+ typically suboptimal form prior to optimization. This new design
+ preserves more IR level information, avoids undoing earlier loop
+ optimizations (particularly hand-optimized loops), and no longer
+ strongly depends on the code generator rewriting loops a second time
+ in a now optimal form--an intractable problem.</p>
+
+<p>The original behavior can be restored with -mllvm -enable-iv-rewrite;
+ however, support for this mode will be short lived. As such, bug
+ reports should be filed for any significant performance regressions
+ when moving from -mllvm -enable-iv-rewrite to the 3.0 default mode.</p>
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