From f94d12b6108b944199b715f31f25a022f75d2feb Mon Sep 17 00:00:00 2001 From: Yichao Yu Date: Sat, 10 Jun 2017 08:45:13 -0400 Subject: [PATCH 4/4] Enable support for floating-point division reductions Similar to fsub, fdiv can also be vectorized using fmul. --- lib/Transforms/Utils/LoopUtils.cpp | 1 + test/Transforms/LoopVectorize/float-reduction.ll | 22 ++++++++++++++++++++++ 2 files changed, 23 insertions(+) diff --git a/lib/Transforms/Utils/LoopUtils.cpp b/lib/Transforms/Utils/LoopUtils.cpp index 3c522786641..a4aced53a95 100644 --- a/lib/Transforms/Utils/LoopUtils.cpp +++ b/lib/Transforms/Utils/LoopUtils.cpp @@ -451,6 +451,7 @@ RecurrenceDescriptor::isRecurrenceInstr(Instruction *I, RecurrenceKind Kind, return InstDesc(Kind == RK_IntegerOr, I); case Instruction::Xor: return InstDesc(Kind == RK_IntegerXor, I); + case Instruction::FDiv: case Instruction::FMul: return InstDesc(Kind == RK_FloatMult, I, UAI); case Instruction::FSub: diff --git a/test/Transforms/LoopVectorize/float-reduction.ll b/test/Transforms/LoopVectorize/float-reduction.ll index f3b95d0ead7..669c54d55a2 100644 --- a/test/Transforms/LoopVectorize/float-reduction.ll +++ b/test/Transforms/LoopVectorize/float-reduction.ll @@ -44,3 +44,25 @@ for.body: ; preds = %for.body, %entry for.end: ; preds = %for.body ret float %sub } + +;CHECK-LABEL: @foodiv( +;CHECK: fdiv fast <4 x float> +;CHECK: ret +define float @foodiv(float* nocapture %A, i32* nocapture %n) nounwind uwtable readonly ssp { +entry: + br label %for.body + +for.body: ; preds = %for.body, %entry + %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] + %sum.04 = phi float [ 1.000000e+00, %entry ], [ %sub, %for.body ] + %arrayidx = getelementptr inbounds float, float* %A, i64 %indvars.iv + %0 = load float, float* %arrayidx, align 4 + %sub = fdiv fast float %sum.04, %0 + %indvars.iv.next = add i64 %indvars.iv, 1 + %lftr.wideiv = trunc i64 %indvars.iv.next to i32 + %exitcond = icmp eq i32 %lftr.wideiv, 200 + br i1 %exitcond, label %for.end, label %for.body + +for.end: ; preds = %for.body + ret float %sub +} -- 2.14.1