[llvm] r294973 - Revert "[LV] Extend trunc optimization to all IVs with constant integer steps"
Matthew Simpson via llvm-commits
llvm-commits at lists.llvm.org
Mon Feb 13 10:02:36 PST 2017
Author: mssimpso
Date: Mon Feb 13 12:02:35 2017
New Revision: 294973
URL: http://llvm.org/viewvc/llvm-project?rev=294973&view=rev
Log:
Revert "[LV] Extend trunc optimization to all IVs with constant integer steps"
This reverts commit r294967. This patch caused execution time slowdowns in a
few LLVM test-suite tests, as reported by the clang-cmake-aarch64-quick bot.
I'm reverting to investigate.
Modified:
llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp
llvm/trunk/test/Transforms/LoopVectorize/induction.ll
llvm/trunk/test/Transforms/LoopVectorize/reverse_iter.ll
Modified: llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp?rev=294973&r1=294972&r2=294973&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp (original)
+++ llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp Mon Feb 13 12:02:35 2017
@@ -4879,15 +4879,12 @@ void InnerLoopVectorizer::vectorizeBlock
// induction variable. Notice that we can only optimize the 'trunc' case
// because (a) FP conversions lose precision, (b) sext/zext may wrap, and
// (c) other casts depend on pointer size.
- if (auto *Trunc = dyn_cast<TruncInst>(CI))
- if (auto *Phi = dyn_cast<PHINode>(Trunc->getOperand(0))) {
- auto II = Legal->getInductionVars()->find(Phi);
- if (II != Legal->getInductionVars()->end())
- if (II->second.getConstIntStepValue()) {
- widenIntInduction(Phi, Trunc);
- break;
- }
- }
+ auto ID = Legal->getInductionVars()->lookup(OldInduction);
+ if (isa<TruncInst>(CI) && CI->getOperand(0) == OldInduction &&
+ ID.getConstIntStepValue()) {
+ widenIntInduction(OldInduction, cast<TruncInst>(CI));
+ break;
+ }
/// Vectorize casts.
Type *DestTy =
@@ -7227,17 +7224,12 @@ unsigned LoopVectorizationCostModel::get
case Instruction::Trunc:
case Instruction::FPTrunc:
case Instruction::BitCast: {
- // We optimize the truncation of induction variables having constant
- // integer steps. The cost of these truncations is the same as the scalar
- // operation.
- if (auto *Trunc = dyn_cast<TruncInst>(I))
- if (auto *Phi = dyn_cast<PHINode>(Trunc->getOperand(0))) {
- auto II = Legal->getInductionVars()->find(Phi);
- if (II != Legal->getInductionVars()->end())
- if (II->second.getConstIntStepValue())
- return TTI.getCastInstrCost(Instruction::Trunc, Trunc->getDestTy(),
- Trunc->getSrcTy());
- }
+ // We optimize the truncation of induction variable.
+ // The cost of these is the same as the scalar operation.
+ if (I->getOpcode() == Instruction::Trunc &&
+ Legal->isInductionVariable(I->getOperand(0)))
+ return TTI.getCastInstrCost(I->getOpcode(), I->getType(),
+ I->getOperand(0)->getType());
Type *SrcScalarTy = I->getOperand(0)->getType();
Type *SrcVecTy = ToVectorTy(SrcScalarTy, VF);
Modified: llvm/trunk/test/Transforms/LoopVectorize/induction.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopVectorize/induction.ll?rev=294973&r1=294972&r2=294973&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/induction.ll (original)
+++ llvm/trunk/test/Transforms/LoopVectorize/induction.ll Mon Feb 13 12:02:35 2017
@@ -773,34 +773,3 @@ for.body:
exit:
ret void
}
-
-; CHECK-LABEL: @non_primary_iv_trunc(
-; CHECK: vector.body:
-; CHECK-NEXT: %index = phi i64 [ 0, %vector.ph ], [ %index.next, %vector.body ]
-; CHECK: [[VEC_IND:%.*]] = phi <2 x i32> [ <i32 0, i32 2>, %vector.ph ], [ [[VEC_IND_NEXT:%.*]], %vector.body ]
-; CHECK: [[TMP3:%.*]] = add i64 %index, 0
-; CHECK-NEXT: [[TMP4:%.*]] = getelementptr inbounds i32, i32* %a, i64 [[TMP3]]
-; CHECK-NEXT: [[TMP5:%.*]] = getelementptr i32, i32* [[TMP4]], i32 0
-; CHECK-NEXT: [[TMP6:%.*]] = bitcast i32* [[TMP5]] to <2 x i32>*
-; CHECK-NEXT: store <2 x i32> [[VEC_IND]], <2 x i32>* [[TMP6]], align 4
-; CHECK-NEXT: %index.next = add i64 %index, 2
-; CHECK: [[VEC_IND_NEXT]] = add <2 x i32> [[VEC_IND]], <i32 4, i32 4>
-; CHECK: br i1 {{.*}}, label %middle.block, label %vector.body
-define void @non_primary_iv_trunc(i32* %a, i64 %n) {
-entry:
- br label %for.body
-
-for.body:
- %i = phi i64 [ %i.next, %for.body ], [ 0, %entry ]
- %j = phi i64 [ %j.next, %for.body ], [ 0, %entry ]
- %tmp0 = getelementptr inbounds i32, i32* %a, i64 %i
- %tmp1 = trunc i64 %j to i32
- store i32 %tmp1, i32* %tmp0, align 4
- %i.next = add nuw nsw i64 %i, 1
- %j.next = add nuw nsw i64 %j, 2
- %cond = icmp slt i64 %i.next, %n
- br i1 %cond, label %for.body, label %for.end
-
-for.end:
- ret void
-}
Modified: llvm/trunk/test/Transforms/LoopVectorize/reverse_iter.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopVectorize/reverse_iter.ll?rev=294973&r1=294972&r2=294973&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/reverse_iter.ll (original)
+++ llvm/trunk/test/Transforms/LoopVectorize/reverse_iter.ll Mon Feb 13 12:02:35 2017
@@ -2,8 +2,7 @@
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"
-; PR15882: This test ensures that we do not produce wrapping arithmetic when
-; creating constant reverse step vectors.
+; Make sure that the reverse iterators are calculated using 64bit arithmetic, not 32.
;
; int foo(int n, int *A) {
; int sum;
@@ -14,7 +13,7 @@ target datalayout = "e-p:64:64:64-i1:8:8
;
;CHECK-LABEL: @foo(
-;CHECK: <i32 0, i32 -1, i32 -2, i32 -3>
+;CHECK: <i64 0, i64 -1, i64 -2, i64 -3>
;CHECK: ret
define i32 @foo(i32 %n, i32* nocapture %A) {
%1 = icmp sgt i32 %n, 0
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