Index: include/llvm/Analysis/DependenceAnalysis.h =================================================================== --- include/llvm/Analysis/DependenceAnalysis.h +++ include/llvm/Analysis/DependenceAnalysis.h @@ -41,6 +41,7 @@ #define LLVM_ANALYSIS_DEPENDENCEANALYSIS_H #include "llvm/ADT/SmallBitVector.h" +#include "llvm/ADT/ArrayRef.h" #include "llvm/IR/Instructions.h" #include "llvm/Pass.h" @@ -520,11 +521,11 @@ /// in LoopNest. bool isLoopInvariant(const SCEV *Expression, const Loop *LoopNest) const; - /// Makes sure both subscripts (i.e. Pair->Src and Pair->Dst) share the same - /// integer type by sign-extending one of them when necessary. + /// Makes sure all subscript pairs share the same integer type by + /// sign-extending as necessary. /// Sign-extending a subscript is safe because getelementptr assumes the - /// array subscripts are signed. - void unifySubscriptType(Subscript *Pair); + /// array subscripts are signed. + void unifySubscriptType(ArrayRef Pairs); /// removeMatchingExtensions - Examines a subscript pair. /// If the source and destination are identically sign (or zero) Index: lib/Analysis/DependenceAnalysis.cpp =================================================================== --- lib/Analysis/DependenceAnalysis.cpp +++ lib/Analysis/DependenceAnalysis.cpp @@ -779,23 +779,56 @@ } } -void DependenceAnalysis::unifySubscriptType(Subscript *Pair) { - const SCEV *Src = Pair->Src; - const SCEV *Dst = Pair->Dst; - IntegerType *SrcTy = dyn_cast(Src->getType()); - IntegerType *DstTy = dyn_cast(Dst->getType()); - if (SrcTy == nullptr || DstTy == nullptr) { - assert(SrcTy == DstTy && "This function only unify integer types and " - "expect Src and Dst share the same type " - "otherwise."); - return; - } - if (SrcTy->getBitWidth() > DstTy->getBitWidth()) { - // Sign-extend Dst to typeof(Src) if typeof(Src) is wider than typeof(Dst). - Pair->Dst = SE->getSignExtendExpr(Dst, SrcTy); - } else if (SrcTy->getBitWidth() < DstTy->getBitWidth()) { - // Sign-extend Src to typeof(Dst) if typeof(Dst) is wider than typeof(Src). - Pair->Src = SE->getSignExtendExpr(Src, DstTy); +void DependenceAnalysis::unifySubscriptType(ArrayRef Pairs) { + + unsigned widestWidthSeen = 0; + Type *widestType; + + // Go through each pair and find the widest bit to which we need + // to extend all of them. + for (unsigned i = 0; i < Pairs.size(); i++) { + const SCEV *Src = Pairs[i]->Src; + const SCEV *Dst = Pairs[i]->Dst; + IntegerType *SrcTy = dyn_cast(Src->getType()); + IntegerType *DstTy = dyn_cast(Dst->getType()); + if (SrcTy == nullptr || DstTy == nullptr) { + assert(SrcTy == DstTy && "This function only unify integer types and " + "expect Src and Dst share the same type " + "otherwise."); + continue; + } + if (SrcTy->getBitWidth() > widestWidthSeen) { + widestWidthSeen = SrcTy->getBitWidth(); + widestType = SrcTy; + } + if (DstTy->getBitWidth() > widestWidthSeen) { + widestWidthSeen = DstTy->getBitWidth(); + widestType = DstTy; + } + } + + + assert(widestWidthSeen > 0); + + // Now extend each pair to the widest seen. + for (unsigned i = 0; i < Pairs.size(); i++) { + const SCEV *Src = Pairs[i]->Src; + const SCEV *Dst = Pairs[i]->Dst; + IntegerType *SrcTy = dyn_cast(Src->getType()); + IntegerType *DstTy = dyn_cast(Dst->getType()); + if (SrcTy == nullptr || DstTy == nullptr) { + assert(SrcTy == DstTy && "This function only unify integer types and " + "expect Src and Dst share the same type " + "otherwise."); + continue; + } + if (SrcTy->getBitWidth() < widestWidthSeen) + // Sign-extend Src to widestType + Pairs[i]->Src = SE->getSignExtendExpr(Src, widestType); + if (DstTy->getBitWidth() < widestWidthSeen) { + // Sign-extend Dst to widestType + Pairs[i]->Dst = SE->getSignExtendExpr(Dst, widestType); + } } } @@ -2919,7 +2952,7 @@ // return the coefficient (the step) // corresponding to the specified loop. // If there isn't one, return 0. -// For example, given a*i + b*j + c*k, zeroing the coefficient +// For example, given a*i + b*j + c*k, finding the coefficient // corresponding to the j loop would yield b. const SCEV *DependenceAnalysis::findCoefficient(const SCEV *Expr, const Loop *TargetLoop) const { @@ -3556,13 +3589,16 @@ SmallBitVector Sivs(Pairs); SmallBitVector Mivs(Pairs); SmallBitVector ConstrainedLevels(MaxLevels + 1); + SmallVector PairsInGroup; for (int SJ = Group.find_first(); SJ >= 0; SJ = Group.find_next(SJ)) { DEBUG(dbgs() << SJ << " "); if (Pair[SJ].Classification == Subscript::SIV) Sivs.set(SJ); else Mivs.set(SJ); + PairsInGroup.push_back(&Pair[SJ]); } + unifySubscriptType(PairsInGroup); DEBUG(dbgs() << "}\n"); while (Sivs.any()) { bool Changed = false; Index: test/Analysis/DependenceAnalysis/NonCanonicalizedSubscript.ll =================================================================== --- test/Analysis/DependenceAnalysis/NonCanonicalizedSubscript.ll +++ test/Analysis/DependenceAnalysis/NonCanonicalizedSubscript.ll @@ -38,3 +38,73 @@ for.end: ret void } + +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +; unsigned i, j; +; for (i = 1; i < SIZE; i++) { +; for (j = i; j < SIZE; j++) { +; a[i][j] = a[i+1][j-1] + 2; +; } +; } +; Extends the previous example to coupled MIV subscripts. + + +@a = global [10004 x [10004 x i32]] zeroinitializer, align 16 + +; Function Attrs: nounwind uwtable +define void @coupled_miv_type_mismatch(i32 %n) #0 { +; CHECK-LABEL: 'Dependence Analysis' for function 'coupled_miv_type_mismatch' +; DELIN-LABEL: 'Dependence Analysis' for function 'coupled_miv_type_mismatch' +entry: + br label %for.cond + +; CHECK: da analyze - input [0 *]! +; CHECK: da analyze - anti [1 *]! +; CHECK: da analyze - none! +; DELIN: da analyze - input [0 *]! +; DELIN: da analyze - anti [1 *]! +; DELIN: da analyze - none! +for.cond: ; preds = %for.inc11, %entry + %indvars.iv11 = phi i64 [ %indvars.iv.next12, %for.inc11 ], [ 1, %entry ] + %exitcond14 = icmp ne i64 %indvars.iv11, 10000 + br i1 %exitcond14, label %for.cond1.preheader, label %for.end13 + +for.cond1.preheader: ; preds = %for.cond + %0 = trunc i64 %indvars.iv11 to i32 + br label %for.cond1 + +for.cond1: ; preds = %for.cond1.preheader, %for.body3 + %indvars.iv8 = phi i64 [ %indvars.iv11, %for.cond1.preheader ], [ %indvars.iv.next9, %for.body3 ] + %j.0 = phi i32 [ %inc, %for.body3 ], [ %0, %for.cond1.preheader ] + %lftr.wideiv = trunc i64 %indvars.iv8 to i32 + %exitcond = icmp ne i32 %lftr.wideiv, 10000 + br i1 %exitcond, label %for.body3, label %for.inc11 + +for.body3: ; preds = %for.cond1 + %sub = add nsw i32 %j.0, -1 + %idxprom = zext i32 %sub to i64 + %1 = add nuw nsw i64 %indvars.iv11, 1 + %arrayidx5 = getelementptr inbounds [10004 x [10004 x i32]], [10004 x [10004 x i32]]* @a, i64 0, i64 %1, i64 %idxprom + %2 = load i32, i32* %arrayidx5, align 4 + %add6 = add nsw i32 %2, 2 + %arrayidx10 = getelementptr inbounds [10004 x [10004 x i32]], [10004 x [10004 x i32]]* @a, i64 0, i64 %indvars.iv11, i64 %indvars.iv8 + store i32 %add6, i32* %arrayidx10, align 4 + %indvars.iv.next9 = add nuw nsw i64 %indvars.iv8, 1 + %inc = add nuw nsw i32 %j.0, 1 + br label %for.cond1 + +for.inc11: ; preds = %for.cond1 + %indvars.iv.next12 = add nuw nsw i64 %indvars.iv11, 1 + br label %for.cond + +for.end13: ; preds = %for.cond + ret void +} + +attributes #0 = { nounwind uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+sse,+sse2" "unsafe-fp-math"="false" "use-soft-float"="false" } + +!llvm.ident = !{!0} + +!0 = !{!"clang version 3.7.0 (https://vaivaswatha@bitbucket.org/compilertree/amd_clang.git 93a05fb75ee3411d24e8b2b184fc766a5318403e) (https://vaivaswatha@bitbucket.org/compilertree/amd_llvm.git 166d93d26efc912b517739f64d054a435e8e95cd)"}