#include "llvm/Instructions.h"
#include "llvm/Function.h"
#include "llvm/Analysis/AliasAnalysis.h"
-#include "llvm/Analysis/Dominators.h"
#include "llvm/Support/CFG.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Target/TargetData.h"
AU.setPreservesAll();
AU.addRequiredTransitive<AliasAnalysis>();
AU.addRequiredTransitive<TargetData>();
- AU.addRequiredTransitive<DominatorTree>();
}
/// getCallSiteDependency - Private helper for finding the local dependencies
continue;
}
- // Don't recur upwards if the current block is unreachable.
- // Instead, mark it as having no dependency on this path,
- // which will block optzns from occuring. For this reason,
- // eliminating unreachable blocks before running a memdep
- // based optimization is recommended.
- DominatorTree& DT = getAnalysis<DominatorTree>();
- if (!DT.isReachableFromEntry(BB)) {
- resp.insert(std::make_pair(BB, None));
- continue;
- }
-
// If we didn't find anything, recurse on the precessors of this block
// Only do this for blocks with a small number of predecessors.
bool predOnStack = false;
DenseMap<BasicBlock*, Value*>::iterator V = Phis.find(BB);
if (V != Phis.end() && !top_level) return V->second;
+ if (!getAnalysis<DominatorTree>().isReachableFromEntry(BB)) {
+ Phis[BB] = UndefValue::get(orig->getType());
+ return UndefValue::get(orig->getType());
+ }
+
BasicBlock* singlePred = BB->getSinglePredecessor();
if (singlePred) {
Value *ret = GetValueForBlock(singlePred, orig, Phis);
--- /dev/null
+; RUN: llvm-as < %s | opt -gvn | llvm-dis | grep undef
+; PR2503
+target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
+target triple = "i686-apple-darwin9.3.0"
+@g_3 = external global i8 ; <i8*> [#uses=2]
+
+define i32 @func_1() nounwind {
+entry:
+ br i1 false, label %ifelse, label %ifthen
+
+ifthen: ; preds = %entry
+ br label %ifend
+
+ifelse: ; preds = %entry
+ %tmp3 = load i8* @g_3 ; <i8> [#uses=0]
+ br label %forcond.thread
+
+forcond.thread: ; preds = %ifelse
+ br label %afterfor
+
+forcond: ; preds = %forinc
+ br i1 false, label %afterfor, label %forbody
+
+forbody: ; preds = %forcond
+ br label %forinc
+
+forinc: ; preds = %forbody
+ br label %forcond
+
+afterfor: ; preds = %forcond, %forcond.thread
+ %tmp10 = load i8* @g_3 ; <i8> [#uses=0]
+ br label %ifend
+
+ifend: ; preds = %afterfor, %ifthen
+ ret i32 0
+}