diff options
5 files changed, 195 insertions, 7 deletions
diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp index 056886f80e6..aa722dbb286 100644 --- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp +++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp @@ -1989,7 +1989,34 @@ linearFunctionTestReplace(Loop *L, DEBUG(dbgs() << " Widen RHS:\t" << *ExitCnt << "\n"); } else { + // We try to extend trip count first. If that doesn't work we truncate IV. + // Zext(trunc(IV)) == IV implies equivalence of the following two: + // Trunc(IV) == ExitCnt and IV == zext(ExitCnt). Similarly for sext. If + // one of the two holds, extend the trip count, otherwise we truncate IV. + bool Extended = false; + const SCEV *IV = SE->getSCEV(CmpIndVar); + const SCEV *ZExtTrunc = + SE->getZeroExtendExpr(SE->getTruncateExpr(SE->getSCEV(CmpIndVar), + ExitCnt->getType()), + CmpIndVar->getType()); + + if (ZExtTrunc == IV) { + Extended = true; + ExitCnt = Builder.CreateZExt(ExitCnt, IndVar->getType(), + "wide.trip.count"); + } else { + const SCEV *SExtTrunc = + SE->getSignExtendExpr(SE->getTruncateExpr(SE->getSCEV(CmpIndVar), + ExitCnt->getType()), + CmpIndVar->getType()); + if (SExtTrunc == IV) { + Extended = true; + ExitCnt = Builder.CreateSExt(ExitCnt, IndVar->getType(), + "wide.trip.count"); + } + } + if (!Extended) CmpIndVar = Builder.CreateTrunc(CmpIndVar, ExitCnt->getType(), "lftr.wideiv"); } diff --git a/llvm/test/Transforms/IndVarSimplify/elim-extend.ll b/llvm/test/Transforms/IndVarSimplify/elim-extend.ll index 8daac23ea74..6b6d5974165 100644 --- a/llvm/test/Transforms/IndVarSimplify/elim-extend.ll +++ b/llvm/test/Transforms/IndVarSimplify/elim-extend.ll @@ -41,6 +41,8 @@ entry: br i1 %precond, label %loop, label %return ; CHECK: loop: ; CHECK-NOT: sext +; CHECK: wide.trip.count = sext +; CHECK-NOT: sext ; CHECK: exit: loop: %iv = phi i32 [ %postiv, %loop ], [ %init, %entry ] diff --git a/llvm/test/Transforms/IndVarSimplify/iv-widen-elim-ext.ll b/llvm/test/Transforms/IndVarSimplify/iv-widen-elim-ext.ll index 97635b560d6..763156d16c6 100644 --- a/llvm/test/Transforms/IndVarSimplify/iv-widen-elim-ext.ll +++ b/llvm/test/Transforms/IndVarSimplify/iv-widen-elim-ext.ll @@ -1,4 +1,4 @@ -; RUN: opt < %s -indvars -S | FileCheck %s +; RUN: opt < %s -indvars -S | FileCheck %s --implicit-check-not sext --implicit-check-not zext target datalayout = "p:64:64:64-n32:64" @@ -7,8 +7,8 @@ target datalayout = "p:64:64:64-n32:64" ; the IV is considered signed or unsigned. define void @foo(i32* %A, i32* %B, i32* %C, i32 %N) { ; CHECK-LABEL: @foo( -; CHECK-NOT: zext -; CHECK-NOT: sext +; CHECK: wide.trip.count = zext +; CHECK: ret void entry: %cmp1 = icmp slt i32 0, %N br i1 %cmp1, label %for.body.lr.ph, label %for.end @@ -45,8 +45,8 @@ for.end: ; preds = %for.cond.for.end_cr define void @foo1(i32* %A, i32* %B, i32* %C, i32 %N) { ; CHECK-LABEL: @foo1( -; CHECK-NOT: zext -; CHECK-NOT: sext +; CHECK: wide.trip.count = zext +; CHECK: ret void entry: %cmp1 = icmp slt i32 0, %N br i1 %cmp1, label %for.body.lr.ph, label %for.end diff --git a/llvm/test/Transforms/IndVarSimplify/lftr-wide-trip-count.ll b/llvm/test/Transforms/IndVarSimplify/lftr-wide-trip-count.ll new file mode 100644 index 00000000000..25c91ddef81 --- /dev/null +++ b/llvm/test/Transforms/IndVarSimplify/lftr-wide-trip-count.ll @@ -0,0 +1,158 @@ +; RUN: opt -S -indvars < %s | FileCheck %s + +; Provide legal integer types. +target datalayout = "n8:16:32:64" + + +define void @test1(float* %autoc, + float* %data, + float %d, i32 %data_len, i32 %sample) nounwind { +entry: + %sub = sub i32 %data_len, %sample + %cmp4 = icmp eq i32 %data_len, %sample + br i1 %cmp4, label %for.end, label %for.body + +for.body: ; preds = %entry, %for.body + %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 68719476736, %entry ] + %temp = trunc i64 %indvars.iv to i32 + %add = add i32 %temp, %sample + %idxprom = zext i32 %add to i64 + %arrayidx = getelementptr inbounds float, float* %data, i64 %idxprom + %temp1 = load float, float* %arrayidx, align 4 + %mul = fmul float %temp1, %d + %arrayidx2 = getelementptr inbounds float, float* %autoc, i64 %indvars.iv + %temp2 = load float, float* %arrayidx2, align 4 + %add3 = fadd float %temp2, %mul + store float %add3, float* %arrayidx2, align 4 + %indvars.iv.next = add i64 %indvars.iv, 1 + %temp3 = trunc i64 %indvars.iv.next to i32 + %cmp = icmp ult i32 %temp3, %sub + br i1 %cmp, label %for.body, label %for.end + +for.end: ; preds = %for.body, %entry + ret void + +; CHECK-LABEL: @test1( + +; With the given initial value for IV, it is not legal to widen +; trip count to IV size +; CHECK: %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 +; CHECK: %lftr.wideiv = trunc i64 %indvars.iv.next to i32 +; CHECK: %exitcond = icmp ne i32 %lftr.wideiv, %sub +; CHECK: br i1 %exitcond, label %for.body, label %for.end.loopexit +} + +define float @test2(float* %a, + float* %b, + i32 zeroext %m) local_unnamed_addr #0 { +entry: + %cmp5 = icmp ugt i32 %m, 500 + br i1 %cmp5, label %for.body.preheader, label %for.end + +for.body.preheader: ; preds = %entry + br label %for.body + +for.body: ; preds = %for.body.preheader, %for.body + %sum.07 = phi float [ %add, %for.body ], [ 0.000000e+00, %for.body.preheader ] + %i.06 = phi i32 [ %inc, %for.body ], [ 500, %for.body.preheader ] + %idxprom = zext i32 %i.06 to i64 + %arrayidx = getelementptr inbounds float, float* %b, i64 %idxprom + %temp = load float, float* %arrayidx, align 4 + %arrayidx2 = getelementptr inbounds float, float* %a, i64 %idxprom + %temp1 = load float, float* %arrayidx2, align 4 + %mul = fmul float %temp, %temp1 + %add = fadd float %sum.07, %mul + %inc = add i32 %i.06, 1 + %cmp = icmp ult i32 %inc, %m + br i1 %cmp, label %for.body, label %for.end.loopexit + +for.end.loopexit: ; preds = %for.body + br label %for.end + +for.end: ; preds = %for.end.loopexit, %entry + %sum.0.lcssa = phi float [ 0.000000e+00, %entry ], [ %add, %for.end.loopexit ] + ret float %sum.0.lcssa + +; CHECK-LABEL: @test2( +; Trip count should be widened and LFTR should canonicalize the condition +; CHECK: %wide.trip.count = zext +; CHECK: %exitcond = icmp ne i64 %indvars.iv.next, %wide.trip.count +; CHECK: br i1 %exitcond +} + +define float @test3(float* %b, + i32 signext %m) local_unnamed_addr #0 { +entry: + %cmp5 = icmp sgt i32 %m, -10 + br i1 %cmp5, label %for.body.preheader, label %for.end + +for.body.preheader: ; preds = %entry + br label %for.body + +for.body: ; preds = %for.body.preheader, %for.body + %sum.07 = phi float [ %add1, %for.body ], [ 0.000000e+00, %for.body.preheader ] + %i.06 = phi i32 [ %inc, %for.body ], [ -10, %for.body.preheader ] + %add = add nsw i32 %i.06, 20 + %idxprom = sext i32 %add to i64 + %arrayidx = getelementptr inbounds float, float* %b, i64 %idxprom + %temp = load float, float* %arrayidx, align 4 + %conv = sitofp i32 %i.06 to float + %mul = fmul float %conv, %temp + %add1 = fadd float %sum.07, %mul + %inc = add nsw i32 %i.06, 1 + %cmp = icmp slt i32 %inc, %m + br i1 %cmp, label %for.body, label %for.end.loopexit + +for.end.loopexit: ; preds = %for.body + br label %for.end + +for.end: ; preds = %for.end.loopexit, %entry + %sum.0.lcssa = phi float [ 0.000000e+00, %entry ], [ %add1, %for.end.loopexit ] + ret float %sum.0.lcssa + +; CHECK-LABEL: @test3( +; Trip count should be widened and LFTR should canonicalize the condition +; CHECK: %wide.trip.count = sext +; CHECK: %exitcond = icmp ne i64 %indvars.iv.next, %wide.trip.count +; CHECK: br i1 %exitcond +} + +define float @test4(float* %b, + i32 signext %m) local_unnamed_addr #0 { +entry: + %cmp5 = icmp sgt i32 %m, 10 + br i1 %cmp5, label %for.body.preheader, label %for.end + +for.body.preheader: ; preds = %entry + br label %for.body + +for.body: ; preds = %for.body.preheader, %for.body + %sum.07 = phi float [ %add1, %for.body ], [ 0.000000e+00, %for.body.preheader ] + %i.06 = phi i32 [ %inc, %for.body ], [ 10, %for.body.preheader ] + %add = add nsw i32 %i.06, 20 + %idxprom = sext i32 %add to i64 + %arrayidx = getelementptr inbounds float, float* %b, i64 %idxprom + %temp = load float, float* %arrayidx, align 4 + %conv = sitofp i32 %i.06 to float + %mul = fmul float %conv, %temp + %add1 = fadd float %sum.07, %mul + %inc = add nsw i32 %i.06, 1 + %cmp = icmp slt i32 %inc, %m + br i1 %cmp, label %for.body, label %for.end.loopexit + +for.end.loopexit: ; preds = %for.body + %add1.lcssa = phi float [ %add1, %for.body ] + br label %for.end + +for.end: ; preds = %for.end.loopexit, %entry + %sum.0.lcssa = phi float [ 0.000000e+00, %entry ], [ %add1.lcssa, %for.end.loopexit ] + ret float %sum.0.lcssa + +; CHECK-LABEL: @test4( +; Trip count should be widened and LFTR should canonicalize the condition +; CHECK: %wide.trip.count = zext +; CHECK: %exitcond = icmp ne i64 %indvars.iv.next, %wide.trip.count +; CHECK: br i1 %exitcond +} + + diff --git a/llvm/test/Transforms/IndVarSimplify/ult-sub-to-eq.ll b/llvm/test/Transforms/IndVarSimplify/ult-sub-to-eq.ll index 3c8c98bccb9..6a7e5b70ca1 100644 --- a/llvm/test/Transforms/IndVarSimplify/ult-sub-to-eq.ll +++ b/llvm/test/Transforms/IndVarSimplify/ult-sub-to-eq.ll @@ -33,8 +33,9 @@ for.end: ; preds = %for.body, %entry ; CHECK-LABEL: @test1( ; check that we turn the IV test into an eq. -; CHECK: %lftr.wideiv = trunc i64 %indvars.iv.next to i32 -; CHECK: %exitcond = icmp ne i32 %lftr.wideiv, %su +; CHECK: %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 +; CHECK: %wide.trip.count = zext i32 %sub to i64 +; CHECK: %exitcond = icmp ne i64 %indvars.iv.next, %wide.trip.count ; CHECK: br i1 %exitcond, label %for.body, label %for.end.loopexit } |
