llvm-project/llvm/test/Transforms/LoopVectorize/X86/illegal-parallel-loop-uniform-write.ll
Kerry McLaughlin 0d748b4d32 [LoopVectorize] Extract the last lane from a uniform store
Changes VPReplicateRecipe to extract the last lane from an unconditional,
uniform store instruction. collectLoopUniforms will also add stores to
the list of uniform instructions where Legal->isUniformMemOp is true.

setCostBasedWideningDecision now sets the widening decision for
all uniform memory ops to Scalarize, where previously GatherScatter
may have been chosen for scalable stores.

This fixes an assert ("Cannot yet scalarize uniform stores") in
setCostBasedWideningDecision when we have a loop containing a
uniform i1 store and a scalable VF, which we cannot create a scatter for.

Reviewed By: sdesmalen, david-arm, fhahn

Differential Revision: https://reviews.llvm.org/D112725
2021-11-09 14:43:16 +00:00

231 lines
13 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -loop-vectorize -force-vector-interleave=1 -force-vector-width=4 -dce -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-unknown-linux-gnu"
; PR15794
; incorrect addition of llvm.mem.parallel_loop_access metadata is undefined
; behaviour. Vectorizer ignores the memory dependency checks and goes ahead and
; vectorizes this loop with uniform stores which has an output dependency.
; void foo(int *a, int *b, int k, int m) {
; for (int i = 0; i < m; i++) {
; for (int j = 0; j < m; j++) {
; a[i] = a[i + j + k] + 1; <<<
; }
; b[i] = b[i] + 3;
; }
; }
; Function Attrs: nounwind uwtable
define void @foo(i32* nocapture %a, i32* nocapture %b, i32 %k, i32 %m) #0 {
; CHECK-LABEL: @foo(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[CMP27:%.*]] = icmp sgt i32 [[M:%.*]], 0
; CHECK-NEXT: br i1 [[CMP27]], label [[FOR_BODY3_LR_PH_US_PREHEADER:%.*]], label [[FOR_END15:%.*]]
; CHECK: for.body3.lr.ph.us.preheader:
; CHECK-NEXT: [[TMP0:%.*]] = add i32 [[M]], -1
; CHECK-NEXT: [[TMP1:%.*]] = zext i32 [[K:%.*]] to i64
; CHECK-NEXT: [[TMP2:%.*]] = zext i32 [[TMP0]] to i64
; CHECK-NEXT: [[TMP3:%.*]] = add nuw nsw i64 [[TMP2]], 1
; CHECK-NEXT: br label [[FOR_BODY3_LR_PH_US:%.*]]
; CHECK: for.end.us:
; CHECK-NEXT: [[ARRAYIDX9_US:%.*]] = getelementptr inbounds i32, i32* [[B:%.*]], i64 [[INDVARS_IV33:%.*]]
; CHECK-NEXT: [[TMP4:%.*]] = load i32, i32* [[ARRAYIDX9_US]], align 4, !llvm.mem.parallel_loop_access !0
; CHECK-NEXT: [[ADD10_US:%.*]] = add nsw i32 [[TMP4]], 3
; CHECK-NEXT: store i32 [[ADD10_US]], i32* [[ARRAYIDX9_US]], align 4, !llvm.mem.parallel_loop_access !0
; CHECK-NEXT: [[INDVARS_IV_NEXT34:%.*]] = add i64 [[INDVARS_IV33]], 1
; CHECK-NEXT: [[LFTR_WIDEIV35:%.*]] = trunc i64 [[INDVARS_IV_NEXT34]] to i32
; CHECK-NEXT: [[EXITCOND36:%.*]] = icmp eq i32 [[LFTR_WIDEIV35]], [[M]]
; CHECK-NEXT: br i1 [[EXITCOND36]], label [[FOR_END15_LOOPEXIT:%.*]], label [[FOR_BODY3_LR_PH_US]], !llvm.loop [[LOOP2:![0-9]+]]
; CHECK: for.body3.us:
; CHECK-NEXT: [[INDVARS_IV29:%.*]] = phi i64 [ [[BC_RESUME_VAL:%.*]], [[SCALAR_PH:%.*]] ], [ [[INDVARS_IV_NEXT30:%.*]], [[FOR_BODY3_US:%.*]] ]
; CHECK-NEXT: [[TMP5:%.*]] = trunc i64 [[INDVARS_IV29]] to i32
; CHECK-NEXT: [[ADD4_US:%.*]] = add i32 [[ADD_US:%.*]], [[TMP5]]
; CHECK-NEXT: [[IDXPROM_US:%.*]] = sext i32 [[ADD4_US]] to i64
; CHECK-NEXT: [[ARRAYIDX_US:%.*]] = getelementptr inbounds i32, i32* [[A:%.*]], i64 [[IDXPROM_US]]
; CHECK-NEXT: [[TMP6:%.*]] = load i32, i32* [[ARRAYIDX_US]], align 4, !llvm.mem.parallel_loop_access !0
; CHECK-NEXT: [[ADD5_US:%.*]] = add nsw i32 [[TMP6]], 1
; CHECK-NEXT: store i32 [[ADD5_US]], i32* [[ARRAYIDX7_US:%.*]], align 4, !llvm.mem.parallel_loop_access !0
; CHECK-NEXT: [[INDVARS_IV_NEXT30]] = add i64 [[INDVARS_IV29]], 1
; CHECK-NEXT: [[LFTR_WIDEIV31:%.*]] = trunc i64 [[INDVARS_IV_NEXT30]] to i32
; CHECK-NEXT: [[EXITCOND32:%.*]] = icmp eq i32 [[LFTR_WIDEIV31]], [[M]]
; CHECK-NEXT: br i1 [[EXITCOND32]], label [[FOR_END_US:%.*]], label [[FOR_BODY3_US]], !llvm.loop [[LOOP3:![0-9]+]]
; CHECK: for.body3.lr.ph.us:
; CHECK-NEXT: [[INDVARS_IV33]] = phi i64 [ [[INDVARS_IV_NEXT34]], [[FOR_END_US]] ], [ 0, [[FOR_BODY3_LR_PH_US_PREHEADER]] ]
; CHECK-NEXT: [[TMP7:%.*]] = add i64 [[TMP1]], [[INDVARS_IV33]]
; CHECK-NEXT: [[TMP8:%.*]] = trunc i64 [[TMP7]] to i32
; CHECK-NEXT: [[TMP9:%.*]] = trunc i64 [[INDVARS_IV33]] to i32
; CHECK-NEXT: [[ADD_US]] = add i32 [[TMP9]], [[K]]
; CHECK-NEXT: [[ARRAYIDX7_US]] = getelementptr inbounds i32, i32* [[A]], i64 [[INDVARS_IV33]]
; CHECK-NEXT: [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[TMP3]], 4
; CHECK-NEXT: br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH]], label [[VECTOR_SCEVCHECK:%.*]]
; CHECK: vector.scevcheck:
; CHECK-NEXT: [[TMP10:%.*]] = add i32 [[TMP8]], [[TMP0]]
; CHECK-NEXT: [[TMP11:%.*]] = sub i32 [[TMP8]], [[TMP0]]
; CHECK-NEXT: [[TMP12:%.*]] = icmp sgt i32 [[TMP11]], [[TMP8]]
; CHECK-NEXT: [[TMP13:%.*]] = icmp slt i32 [[TMP10]], [[TMP8]]
; CHECK-NEXT: [[TMP14:%.*]] = select i1 false, i1 [[TMP12]], i1 [[TMP13]]
; CHECK-NEXT: [[TMP15:%.*]] = or i1 false, [[TMP14]]
; CHECK-NEXT: br i1 [[TMP15]], label [[SCALAR_PH]], label [[VECTOR_PH:%.*]]
; CHECK: vector.ph:
; CHECK-NEXT: [[N_MOD_VF:%.*]] = urem i64 [[TMP3]], 4
; CHECK-NEXT: [[N_VEC:%.*]] = sub i64 [[TMP3]], [[N_MOD_VF]]
; CHECK-NEXT: br label [[VECTOR_BODY:%.*]]
; CHECK: vector.body:
; CHECK-NEXT: [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ]
; CHECK-NEXT: [[TMP16:%.*]] = trunc i64 [[INDEX]] to i32
; CHECK-NEXT: [[TMP17:%.*]] = add i32 [[TMP16]], 0
; CHECK-NEXT: [[TMP18:%.*]] = add i32 [[ADD_US]], [[TMP17]]
; CHECK-NEXT: [[TMP19:%.*]] = sext i32 [[TMP18]] to i64
; CHECK-NEXT: [[TMP20:%.*]] = getelementptr inbounds i32, i32* [[A]], i64 [[TMP19]]
; CHECK-NEXT: [[TMP21:%.*]] = getelementptr inbounds i32, i32* [[TMP20]], i32 0
; CHECK-NEXT: [[TMP22:%.*]] = bitcast i32* [[TMP21]] to <4 x i32>*
; CHECK-NEXT: [[WIDE_LOAD:%.*]] = load <4 x i32>, <4 x i32>* [[TMP22]], align 4
; CHECK-NEXT: [[TMP23:%.*]] = add nsw <4 x i32> [[WIDE_LOAD]], <i32 1, i32 1, i32 1, i32 1>
; CHECK-NEXT: [[TMP24:%.*]] = extractelement <4 x i32> [[TMP23]], i32 3
; CHECK-NEXT: store i32 [[TMP24]], i32* [[ARRAYIDX7_US]], align 4, !llvm.mem.parallel_loop_access !0
; CHECK-NEXT: [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 4
; CHECK-NEXT: [[TMP25:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
; CHECK-NEXT: br i1 [[TMP25]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !llvm.loop [[LOOP5:![0-9]+]]
; CHECK: middle.block:
; CHECK-NEXT: [[CMP_N:%.*]] = icmp eq i64 [[TMP3]], [[N_VEC]]
; CHECK-NEXT: br i1 [[CMP_N]], label [[FOR_END_US]], label [[SCALAR_PH]]
; CHECK: scalar.ph:
; CHECK-NEXT: [[BC_RESUME_VAL]] = phi i64 [ [[N_VEC]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY3_LR_PH_US]] ], [ 0, [[VECTOR_SCEVCHECK]] ]
; CHECK-NEXT: br label [[FOR_BODY3_US]]
; CHECK: for.end15.loopexit:
; CHECK-NEXT: br label [[FOR_END15]]
; CHECK: for.end15:
; CHECK-NEXT: ret void
;
entry:
%cmp27 = icmp sgt i32 %m, 0
br i1 %cmp27, label %for.body3.lr.ph.us, label %for.end15
for.end.us: ; preds = %for.body3.us
%arrayidx9.us = getelementptr inbounds i32, i32* %b, i64 %indvars.iv33
%0 = load i32, i32* %arrayidx9.us, align 4, !llvm.mem.parallel_loop_access !3
%add10.us = add nsw i32 %0, 3
store i32 %add10.us, i32* %arrayidx9.us, align 4, !llvm.mem.parallel_loop_access !3
%indvars.iv.next34 = add i64 %indvars.iv33, 1
%lftr.wideiv35 = trunc i64 %indvars.iv.next34 to i32
%exitcond36 = icmp eq i32 %lftr.wideiv35, %m
br i1 %exitcond36, label %for.end15, label %for.body3.lr.ph.us, !llvm.loop !5
for.body3.us: ; preds = %for.body3.us, %for.body3.lr.ph.us
%indvars.iv29 = phi i64 [ 0, %for.body3.lr.ph.us ], [ %indvars.iv.next30, %for.body3.us ]
%1 = trunc i64 %indvars.iv29 to i32
%add4.us = add i32 %add.us, %1
%idxprom.us = sext i32 %add4.us to i64
%arrayidx.us = getelementptr inbounds i32, i32* %a, i64 %idxprom.us
%2 = load i32, i32* %arrayidx.us, align 4, !llvm.mem.parallel_loop_access !3
%add5.us = add nsw i32 %2, 1
store i32 %add5.us, i32* %arrayidx7.us, align 4, !llvm.mem.parallel_loop_access !3
%indvars.iv.next30 = add i64 %indvars.iv29, 1
%lftr.wideiv31 = trunc i64 %indvars.iv.next30 to i32
%exitcond32 = icmp eq i32 %lftr.wideiv31, %m
br i1 %exitcond32, label %for.end.us, label %for.body3.us, !llvm.loop !4
for.body3.lr.ph.us: ; preds = %for.end.us, %entry
%indvars.iv33 = phi i64 [ %indvars.iv.next34, %for.end.us ], [ 0, %entry ]
%3 = trunc i64 %indvars.iv33 to i32
%add.us = add i32 %3, %k
%arrayidx7.us = getelementptr inbounds i32, i32* %a, i64 %indvars.iv33
br label %for.body3.us
for.end15: ; preds = %for.end.us, %entry
ret void
}
; Same test as above, but without the invalid parallel_loop_access metadata.
; Here we can see the vectorizer does the mem dep checks and decides it is
; unsafe to vectorize.
define void @no-par-mem-metadata(i32* nocapture %a, i32* nocapture %b, i32 %k, i32 %m) #0 {
; CHECK-LABEL: @no-par-mem-metadata(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[CMP27:%.*]] = icmp sgt i32 [[M:%.*]], 0
; CHECK-NEXT: br i1 [[CMP27]], label [[FOR_BODY3_LR_PH_US_PREHEADER:%.*]], label [[FOR_END15:%.*]]
; CHECK: for.body3.lr.ph.us.preheader:
; CHECK-NEXT: br label [[FOR_BODY3_LR_PH_US:%.*]]
; CHECK: for.end.us:
; CHECK-NEXT: [[ARRAYIDX9_US:%.*]] = getelementptr inbounds i32, i32* [[B:%.*]], i64 [[INDVARS_IV33:%.*]]
; CHECK-NEXT: [[TMP0:%.*]] = load i32, i32* [[ARRAYIDX9_US]], align 4
; CHECK-NEXT: [[ADD10_US:%.*]] = add nsw i32 [[TMP0]], 3
; CHECK-NEXT: store i32 [[ADD10_US]], i32* [[ARRAYIDX9_US]], align 4
; CHECK-NEXT: [[INDVARS_IV_NEXT34:%.*]] = add i64 [[INDVARS_IV33]], 1
; CHECK-NEXT: [[LFTR_WIDEIV35:%.*]] = trunc i64 [[INDVARS_IV_NEXT34]] to i32
; CHECK-NEXT: [[EXITCOND36:%.*]] = icmp eq i32 [[LFTR_WIDEIV35]], [[M]]
; CHECK-NEXT: br i1 [[EXITCOND36]], label [[FOR_END15_LOOPEXIT:%.*]], label [[FOR_BODY3_LR_PH_US]], !llvm.loop [[LOOP2]]
; CHECK: for.body3.us:
; CHECK-NEXT: [[INDVARS_IV29:%.*]] = phi i64 [ 0, [[FOR_BODY3_LR_PH_US]] ], [ [[INDVARS_IV_NEXT30:%.*]], [[FOR_BODY3_US:%.*]] ]
; CHECK-NEXT: [[TMP1:%.*]] = trunc i64 [[INDVARS_IV29]] to i32
; CHECK-NEXT: [[ADD4_US:%.*]] = add i32 [[ADD_US:%.*]], [[TMP1]]
; CHECK-NEXT: [[IDXPROM_US:%.*]] = sext i32 [[ADD4_US]] to i64
; CHECK-NEXT: [[ARRAYIDX_US:%.*]] = getelementptr inbounds i32, i32* [[A:%.*]], i64 [[IDXPROM_US]]
; CHECK-NEXT: [[TMP2:%.*]] = load i32, i32* [[ARRAYIDX_US]], align 4
; CHECK-NEXT: [[ADD5_US:%.*]] = add nsw i32 [[TMP2]], 1
; CHECK-NEXT: store i32 [[ADD5_US]], i32* [[ARRAYIDX7_US:%.*]], align 4
; CHECK-NEXT: [[INDVARS_IV_NEXT30]] = add i64 [[INDVARS_IV29]], 1
; CHECK-NEXT: [[LFTR_WIDEIV31:%.*]] = trunc i64 [[INDVARS_IV_NEXT30]] to i32
; CHECK-NEXT: [[EXITCOND32:%.*]] = icmp eq i32 [[LFTR_WIDEIV31]], [[M]]
; CHECK-NEXT: br i1 [[EXITCOND32]], label [[FOR_END_US:%.*]], label [[FOR_BODY3_US]], !llvm.loop [[LOOP1:![0-9]+]]
; CHECK: for.body3.lr.ph.us:
; CHECK-NEXT: [[INDVARS_IV33]] = phi i64 [ [[INDVARS_IV_NEXT34]], [[FOR_END_US]] ], [ 0, [[FOR_BODY3_LR_PH_US_PREHEADER]] ]
; CHECK-NEXT: [[TMP3:%.*]] = trunc i64 [[INDVARS_IV33]] to i32
; CHECK-NEXT: [[ADD_US]] = add i32 [[TMP3]], [[K:%.*]]
; CHECK-NEXT: [[ARRAYIDX7_US]] = getelementptr inbounds i32, i32* [[A]], i64 [[INDVARS_IV33]]
; CHECK-NEXT: br label [[FOR_BODY3_US]]
; CHECK: for.end15.loopexit:
; CHECK-NEXT: br label [[FOR_END15]]
; CHECK: for.end15:
; CHECK-NEXT: ret void
;
entry:
%cmp27 = icmp sgt i32 %m, 0
br i1 %cmp27, label %for.body3.lr.ph.us, label %for.end15
for.end.us: ; preds = %for.body3.us
%arrayidx9.us = getelementptr inbounds i32, i32* %b, i64 %indvars.iv33
%0 = load i32, i32* %arrayidx9.us, align 4
%add10.us = add nsw i32 %0, 3
store i32 %add10.us, i32* %arrayidx9.us, align 4
%indvars.iv.next34 = add i64 %indvars.iv33, 1
%lftr.wideiv35 = trunc i64 %indvars.iv.next34 to i32
%exitcond36 = icmp eq i32 %lftr.wideiv35, %m
br i1 %exitcond36, label %for.end15, label %for.body3.lr.ph.us, !llvm.loop !5
for.body3.us: ; preds = %for.body3.us, %for.body3.lr.ph.us
%indvars.iv29 = phi i64 [ 0, %for.body3.lr.ph.us ], [ %indvars.iv.next30, %for.body3.us ]
%1 = trunc i64 %indvars.iv29 to i32
%add4.us = add i32 %add.us, %1
%idxprom.us = sext i32 %add4.us to i64
%arrayidx.us = getelementptr inbounds i32, i32* %a, i64 %idxprom.us
%2 = load i32, i32* %arrayidx.us, align 4
%add5.us = add nsw i32 %2, 1
store i32 %add5.us, i32* %arrayidx7.us, align 4
%indvars.iv.next30 = add i64 %indvars.iv29, 1
%lftr.wideiv31 = trunc i64 %indvars.iv.next30 to i32
%exitcond32 = icmp eq i32 %lftr.wideiv31, %m
br i1 %exitcond32, label %for.end.us, label %for.body3.us, !llvm.loop !4
for.body3.lr.ph.us: ; preds = %for.end.us, %entry
%indvars.iv33 = phi i64 [ %indvars.iv.next34, %for.end.us ], [ 0, %entry ]
%3 = trunc i64 %indvars.iv33 to i32
%add.us = add i32 %3, %k
%arrayidx7.us = getelementptr inbounds i32, i32* %a, i64 %indvars.iv33
br label %for.body3.us
for.end15: ; preds = %for.end.us, %entry
ret void
}
attributes #0 = { nounwind uwtable "less-precise-fpmad"="false" "frame-pointer"="none" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "unsafe-fp-math"="false" "use-soft-float"="false" }
!3 = !{!4, !5}
!4 = !{!4}
!5 = !{!5}