From d6aa89eca5be76dece4b4cd44359e8577e587dff Mon Sep 17 00:00:00 2001 From: Renato Golin Date: Thu, 24 Oct 2013 14:50:51 +0000 Subject: Mark vector loops as already vectorized Make sure we mark all loops (scalar and vector) when vectorizing, so that we don't try to vectorize them anymore. Also, set unroll to 1, since this is what we check for on early exit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193349 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Vectorize/LoopVectorize.cpp | 4 ++ .../Transforms/LoopVectorize/already-vectorized.ll | 46 ++++++++++++++++++++++ test/Transforms/LoopVectorize/vectorize-once.ll | 5 ++- 3 files changed, 53 insertions(+), 2 deletions(-) create mode 100644 test/Transforms/LoopVectorize/already-vectorized.ll diff --git a/lib/Transforms/Vectorize/LoopVectorize.cpp b/lib/Transforms/Vectorize/LoopVectorize.cpp index 72ddb74..317c1ff 100644 --- a/lib/Transforms/Vectorize/LoopVectorize.cpp +++ b/lib/Transforms/Vectorize/LoopVectorize.cpp @@ -801,6 +801,7 @@ struct LoopVectorizeHints { Vals.push_back(LoopID->getOperand(i)); Vals.push_back(createHint(Context, Twine(Prefix(), "width").str(), Width)); + Vals.push_back(createHint(Context, Twine(Prefix(), "unroll").str(), 1)); MDNode *NewLoopID = MDNode::get(Context, Vals); // Set operand 0 to refer to the loop id itself. @@ -1785,6 +1786,9 @@ InnerLoopVectorizer::createEmptyLoop(LoopVectorizationLegality *Legal) { LoopExitBlock = ExitBlock; LoopVectorBody = VecBody; LoopScalarBody = OldBasicBlock; + + LoopVectorizeHints Hints(Lp, true); + Hints.setAlreadyVectorized(Lp); } /// This function returns the identity element (or neutral element) for diff --git a/test/Transforms/LoopVectorize/already-vectorized.ll b/test/Transforms/LoopVectorize/already-vectorized.ll new file mode 100644 index 0000000..885418c --- /dev/null +++ b/test/Transforms/LoopVectorize/already-vectorized.ll @@ -0,0 +1,46 @@ +; RUN: opt < %s -debug-only=loop-vectorize -O3 -S 2>&1 | FileCheck %s +; REQUIRES: asserts +; We want to make sure that we don't even try to vectorize loops again +; The vectorizer used to mark the un-vectorized loop only as already vectorized +; thus, trying to vectorize the vectorized loop again + +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +@a = external global [255 x i32] + +; Function Attrs: nounwind readonly uwtable +define i32 @vect() { +; CHECK: LV: Checking a loop in "vect" +entry: + br label %for.body + +for.body: ; preds = %for.body, %entry +; We need to make sure we did vectorize the loop +; CHECK: LV: Found a loop: for.body +; CHECK: LV: We can vectorize this loop! + %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] + %red.05 = phi i32 [ 0, %entry ], [ %add, %for.body ] + %arrayidx = getelementptr inbounds [255 x i32]* @a, i64 0, i64 %indvars.iv + %0 = load i32* %arrayidx, align 4 + %add = add nsw i32 %0, %red.05 + %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 + %exitcond = icmp eq i64 %indvars.iv.next, 255 + br i1 %exitcond, label %for.end, label %for.body + +; If it did, we have two loops: +; CHECK: vector.body: +; CHECK: br {{.*}} label %vector.body, !llvm.loop [[vect:![0-9]+]] +; CHECK: for.body: +; CHECK: br {{.*}} label %for.body, !llvm.loop [[scalar:![0-9]+]] + +for.end: ; preds = %for.body + ret i32 %add +} + +; Now, we check for the Hint metadata +; CHECK: [[vect]] = metadata !{metadata [[vect]], metadata [[width:![0-9]+]], metadata [[unroll:![0-9]+]]} +; CHECK: [[width]] = metadata !{metadata !"llvm.vectorizer.width", i32 1} +; CHECK: [[unroll]] = metadata !{metadata !"llvm.vectorizer.unroll", i32 1} +; CHECK: [[scalar]] = metadata !{metadata [[scalar]], metadata [[width]], metadata [[unroll]]} + diff --git a/test/Transforms/LoopVectorize/vectorize-once.ll b/test/Transforms/LoopVectorize/vectorize-once.ll index 062c516..7800469 100644 --- a/test/Transforms/LoopVectorize/vectorize-once.ll +++ b/test/Transforms/LoopVectorize/vectorize-once.ll @@ -68,9 +68,10 @@ _ZSt10accumulateIPiiET0_T_S2_S1_.exit: ; preds = %for.body.i, %entry attributes #0 = { nounwind readonly ssp uwtable "fp-contract-model"="standard" "no-frame-pointer-elim" "no-frame-pointer-elim-non-leaf" "realign-stack" "relocation-model"="pic" "ssp-buffers-size"="8" } -; CHECK: !0 = metadata !{metadata !0, metadata !1} +; CHECK: !0 = metadata !{metadata !0, metadata !1, metadata !2} ; CHECK: !1 = metadata !{metadata !"llvm.vectorizer.width", i32 1} -; CHECK: !2 = metadata !{metadata !2, metadata !1} +; CHECK: !2 = metadata !{metadata !"llvm.vectorizer.unroll", i32 1} +; CHECK: !3 = metadata !{metadata !3, metadata !1, metadata !2} !0 = metadata !{metadata !0, metadata !1} !1 = metadata !{metadata !"llvm.vectorizer.width", i32 1} -- cgit v1.1