[llvm-commits] [llvm] r167084 - in /llvm/trunk: lib/Transforms/Vectorize/LoopVectorize.cpp test/Transforms/LoopVectorize/X86/avx1.ll test/Transforms/LoopVectorize/start-non-zero.ll
Nadav Rotem
nrotem at apple.com
Tue Oct 30 17:45:26 PDT 2012
Author: nadav
Date: Tue Oct 30 19:45:26 2012
New Revision: 167084
URL: http://llvm.org/viewvc/llvm-project?rev=167084&view=rev
Log:
Add support for loops that don't start with Zero.
This is important for loops in the LAPACK test-suite.
These loops start at 1 because they are auto-converted from fortran.
Added:
llvm/trunk/test/Transforms/LoopVectorize/X86/avx1.ll
llvm/trunk/test/Transforms/LoopVectorize/start-non-zero.ll
Modified:
llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp
Modified: llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp?rev=167084&r1=167083&r2=167084&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp (original)
+++ llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp Tue Oct 30 19:45:26 2012
@@ -633,6 +633,10 @@
BasicBlock *ExitBlock = OrigLoop->getExitBlock();
assert(ExitBlock && "Must have an exit block");
+ // The loop index does not have to start at Zero. It starts with this value.
+ OldInduction = Legal->getInduction();
+ Value *StartIdx = OldInduction->getIncomingValueForBlock(BypassBlock);
+
assert(OrigLoop->getNumBlocks() == 1 && "Invalid loop");
assert(BypassBlock && "Invalid loop structure");
@@ -648,7 +652,6 @@
"scalar.preheader");
// Find the induction variable.
BasicBlock *OldBasicBlock = OrigLoop->getHeader();
- OldInduction = Legal->getInduction();
assert(OldInduction && "We must have a single phi node.");
Type *IdxTy = OldInduction->getType();
@@ -658,7 +661,6 @@
// Generate the induction variable.
Induction = Builder.CreatePHI(IdxTy, 2, "index");
- Constant *Zero = ConstantInt::get(IdxTy, 0);
Constant *Step = ConstantInt::get(IdxTy, VF);
// Find the loop boundaries.
@@ -682,15 +684,22 @@
// Count holds the overall loop count (N).
Value *Count = Exp.expandCodeFor(ExitCount, Induction->getType(), Loc);
+
+ // Add the start index to the loop count to get the new end index.
+ Value *IdxEnd = BinaryOperator::CreateAdd(Count, StartIdx, "end.idx", Loc);
+
// Now we need to generate the expression for N - (N % VF), which is
// the part that the vectorized body will execute.
Constant *CIVF = ConstantInt::get(IdxTy, VF);
Value *R = BinaryOperator::CreateURem(Count, CIVF, "n.mod.vf", Loc);
Value *CountRoundDown = BinaryOperator::CreateSub(Count, R, "n.vec", Loc);
+ Value *IdxEndRoundDown = BinaryOperator::CreateAdd(CountRoundDown, StartIdx,
+ "end.idx.rnd.down", Loc);
// Now, compare the new count to zero. If it is zero, jump to the scalar part.
Value *Cmp = CmpInst::Create(Instruction::ICmp, CmpInst::ICMP_EQ,
- CountRoundDown, ConstantInt::getNullValue(IdxTy),
+ IdxEndRoundDown,
+ StartIdx,
"cmp.zero", Loc);
BranchInst::Create(MiddleBlock, VectorPH, Cmp, Loc);
// Remove the old terminator.
@@ -699,8 +708,8 @@
// Add a check in the middle block to see if we have completed
// all of the iterations in the first vector loop.
// If (N - N%VF) == N, then we *don't* need to run the remainder.
- Value *CmpN = CmpInst::Create(Instruction::ICmp, CmpInst::ICMP_EQ, Count,
- CountRoundDown, "cmp.n",
+ Value *CmpN = CmpInst::Create(Instruction::ICmp, CmpInst::ICMP_EQ, IdxEnd,
+ IdxEndRoundDown, "cmp.n",
MiddleBlock->getTerminator());
BranchInst::Create(ExitBlock, ScalarPH, CmpN, MiddleBlock->getTerminator());
@@ -709,10 +718,10 @@
// Create i+1 and fill the PHINode.
Value *NextIdx = Builder.CreateAdd(Induction, Step, "index.next");
- Induction->addIncoming(Zero, VectorPH);
+ Induction->addIncoming(StartIdx, VectorPH);
Induction->addIncoming(NextIdx, VecBody);
// Create the compare.
- Value *ICmp = Builder.CreateICmpEQ(NextIdx, CountRoundDown);
+ Value *ICmp = Builder.CreateICmpEQ(NextIdx, IdxEndRoundDown);
Builder.CreateCondBr(ICmp, MiddleBlock, VecBody);
// Now we have two terminators. Remove the old one from the block.
@@ -720,7 +729,7 @@
// Fix the scalar body iteration count.
unsigned BlockIdx = OldInduction->getBasicBlockIndex(ScalarPH);
- OldInduction->setIncomingValue(BlockIdx, CountRoundDown);
+ OldInduction->setIncomingValue(BlockIdx, IdxEndRoundDown);
// Get ready to start creating new instructions into the vectorized body.
Builder.SetInsertPoint(VecBody->getFirstInsertionPt());
@@ -748,7 +757,6 @@
LoopBypassBlock = BypassBlock;
}
-
/// This function returns the identity element (or neutral element) for
/// the operation K.
static unsigned
@@ -1518,10 +1526,9 @@
return false;
}
const SCEV *Step = AR->getStepRecurrence(*SE);
- const SCEV *Start = AR->getStart();
- if (!Step->isOne() || !Start->isZero()) {
- DEBUG(dbgs() << "LV: PHI does not start at zero or steps by one.\n");
+ if (!Step->isOne()) {
+ DEBUG(dbgs() << "LV: PHI stride does not equal one.\n");
return false;
}
return true;
Added: llvm/trunk/test/Transforms/LoopVectorize/X86/avx1.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopVectorize/X86/avx1.ll?rev=167084&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/X86/avx1.ll (added)
+++ llvm/trunk/test/Transforms/LoopVectorize/X86/avx1.ll Tue Oct 30 19:45:26 2012
@@ -0,0 +1,49 @@
+; RUN: opt < %s -loop-vectorize -mtriple=x86_64-apple-macosx10.8.0 -mcpu=corei7-avx -S | FileCheck %s
+
+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-apple-macosx10.8.0"
+
+;CHECK: @read_mod_write_single_ptr
+;CHECK: load <8 x float>
+;CHECK: ret i32
+define i32 @read_mod_write_single_ptr(float* nocapture %a, i32 %n) nounwind uwtable ssp {
+ %1 = icmp sgt i32 %n, 0
+ br i1 %1, label %.lr.ph, label %._crit_edge
+
+.lr.ph: ; preds = %0, %.lr.ph
+ %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %0 ]
+ %2 = getelementptr inbounds float* %a, i64 %indvars.iv
+ %3 = load float* %2, align 4
+ %4 = fmul float %3, 3.000000e+00
+ store float %4, float* %2, align 4
+ %indvars.iv.next = add i64 %indvars.iv, 1
+ %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+ %exitcond = icmp eq i32 %lftr.wideiv, %n
+ br i1 %exitcond, label %._crit_edge, label %.lr.ph
+
+._crit_edge: ; preds = %.lr.ph, %0
+ ret i32 undef
+}
+
+
+;CHECK: @read_mod_i64
+;CHECK: load <8 x i64>
+;CHECK: ret i32
+define i32 @read_mod_i64(i64* nocapture %a, i32 %n) nounwind uwtable ssp {
+ %1 = icmp sgt i32 %n, 0
+ br i1 %1, label %.lr.ph, label %._crit_edge
+
+.lr.ph: ; preds = %0, %.lr.ph
+ %indvars.iv = phi i64 [ %indvars.iv.next, %.lr.ph ], [ 0, %0 ]
+ %2 = getelementptr inbounds i64* %a, i64 %indvars.iv
+ %3 = load i64* %2, align 4
+ %4 = mul i64 %3, 3
+ store i64 %4, i64* %2, align 4
+ %indvars.iv.next = add i64 %indvars.iv, 1
+ %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+ %exitcond = icmp eq i32 %lftr.wideiv, %n
+ br i1 %exitcond, label %._crit_edge, label %.lr.ph
+
+._crit_edge: ; preds = %.lr.ph, %0
+ ret i32 undef
+}
Added: llvm/trunk/test/Transforms/LoopVectorize/start-non-zero.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/LoopVectorize/start-non-zero.ll?rev=167084&view=auto
==============================================================================
--- llvm/trunk/test/Transforms/LoopVectorize/start-non-zero.ll (added)
+++ llvm/trunk/test/Transforms/LoopVectorize/start-non-zero.ll Tue Oct 30 19:45:26 2012
@@ -0,0 +1,35 @@
+; RUN: opt < %s -loop-vectorize -force-vector-width=4 -instcombine -S | FileCheck %s
+
+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-apple-macosx10.8.0"
+
+;CHECK: @start_at_nonzero
+;CHECK: mul <4 x i32>
+;CHECK: ret i32
+define i32 @start_at_nonzero(i32* nocapture %a, i32 %start, i32 %end) nounwind uwtable ssp {
+entry:
+ %cmp3 = icmp slt i32 %start, %end
+ br i1 %cmp3, label %for.body.lr.ph, label %for.end
+
+for.body.lr.ph: ; preds = %entry
+ %0 = sext i32 %start to i64
+ br label %for.body
+
+for.body: ; preds = %for.body.lr.ph, %for.body
+ %indvars.iv = phi i64 [ %0, %for.body.lr.ph ], [ %indvars.iv.next, %for.body ]
+ %arrayidx = getelementptr inbounds i32* %a, i64 %indvars.iv
+ %1 = load i32* %arrayidx, align 4, !tbaa !0
+ %mul = mul nsw i32 %1, 333
+ store i32 %mul, i32* %arrayidx, align 4, !tbaa !0
+ %indvars.iv.next = add i64 %indvars.iv, 1
+ %2 = trunc i64 %indvars.iv.next to i32
+ %cmp = icmp slt i32 %2, %end
+ br i1 %cmp, label %for.body, label %for.end
+
+for.end: ; preds = %for.body, %entry
+ ret i32 4
+}
+
+!0 = metadata !{metadata !"int", metadata !1}
+!1 = metadata !{metadata !"omnipotent char", metadata !2}
+!2 = metadata !{metadata !"Simple C/C++ TBAA"}
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