1 files changed, 179 insertions, 0 deletions
diff --git a/llvm/test/Transforms/LoopVectorize/runtime-check.ll b/llvm/test/Transforms/LoopVectorize/runtime-check.ll
new file mode 100644
index 00000000000..2a665e56ab0
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/runtime-check.ll
@@ -0,0 +1,179 @@
+; 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 -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"
+
+; Make sure we vectorize this loop:
+; int foo(float *a, float *b, int n) {
+;   for (int i=0; i<n; ++i)
+;     a[i] = b[i] * 3;
+; }
+
+define i32 @foo(float* nocapture %a, float* nocapture %b, i32 %n) nounwind uwtable ssp {
+; CHECK-LABEL: @foo(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[CMP6:%.*]] = icmp sgt i32 [[N:%.*]], 0, !dbg !4
+; CHECK-NEXT:    br i1 [[CMP6]], label [[FOR_BODY_PREHEADER:%.*]], label [[FOR_END:%.*]], !dbg !4
+; CHECK:       for.body.preheader:
+; CHECK-NEXT:    [[TMP0:%.*]] = add i32 [[N]], -1, !dbg !9
+; CHECK-NEXT:    [[TMP1:%.*]] = zext i32 [[TMP0]] to i64, !dbg !9
+; CHECK-NEXT:    [[TMP2:%.*]] = add nuw nsw i64 [[TMP1]], 1, !dbg !9
+; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[TMP2]], 4, !dbg !9
+; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label [[SCALAR_PH:%.*]], label [[VECTOR_MEMCHECK:%.*]], !dbg !9
+; CHECK:       vector.memcheck:
+; CHECK-NEXT:    [[TMP3:%.*]] = add i32 [[N]], -1, !dbg !9
+; CHECK-NEXT:    [[TMP4:%.*]] = zext i32 [[TMP3]] to i64, !dbg !9
+; CHECK-NEXT:    [[TMP5:%.*]] = add nuw nsw i64 [[TMP4]], 1, !dbg !9
+; CHECK-NEXT:    [[SCEVGEP:%.*]] = getelementptr float, float* [[A:%.*]], i64 [[TMP5]], !dbg !9
+; CHECK-NEXT:    [[SCEVGEP4:%.*]] = getelementptr float, float* [[B:%.*]], i64 [[TMP5]], !dbg !9
+; CHECK-NEXT:    [[BOUND0:%.*]] = icmp ugt float* [[SCEVGEP4]], [[A]], !dbg !9
+; CHECK-NEXT:    [[BOUND1:%.*]] = icmp ugt float* [[SCEVGEP]], [[B]], !dbg !9
+; CHECK-NEXT:    [[MEMCHECK_CONFLICT:%.*]] = and i1 [[BOUND0]], [[BOUND1]], !dbg !9
+; CHECK-NEXT:    br i1 [[MEMCHECK_CONFLICT]], label [[SCALAR_PH]], label [[VECTOR_PH:%.*]], !dbg !9
+; CHECK:       vector.ph:
+; CHECK-NEXT:    [[N_VEC:%.*]] = and i64 [[TMP2]], 8589934588, !dbg !9
+; CHECK-NEXT:    br label [[VECTOR_BODY:%.*]], !dbg !9
+; CHECK:       vector.body:
+; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, [[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], [[VECTOR_BODY]] ], !dbg !9
+; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr inbounds float, float* [[B]], i64 [[INDEX]], !dbg !9
+; CHECK-NEXT:    [[TMP8:%.*]] = bitcast float* [[TMP7]] to <4 x float>*, !dbg !9
+; CHECK-NEXT:    [[WIDE_LOAD:%.*]] = load <4 x float>, <4 x float>* [[TMP8]], align 4, !dbg !9, !alias.scope !10
+; CHECK-NEXT:    [[TMP9:%.*]] = fmul <4 x float> [[WIDE_LOAD]], <float 3.000000e+00, float 3.000000e+00, float 3.000000e+00, float 3.000000e+00>, !dbg !9
+; CHECK-NEXT:    [[TMP10:%.*]] = getelementptr inbounds float, float* [[A]], i64 [[INDEX]], !dbg !9
+; CHECK-NEXT:    [[TMP11:%.*]] = bitcast float* [[TMP10]] to <4 x float>*, !dbg !9
+; CHECK-NEXT:    store <4 x float> [[TMP9]], <4 x float>* [[TMP11]], align 4, !dbg !9, !alias.scope !13, !noalias !10
+; CHECK-NEXT:    [[INDEX_NEXT]] = add i64 [[INDEX]], 4, !dbg !9
+; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]], !dbg !9
+; CHECK-NEXT:    br i1 [[TMP12]], label [[MIDDLE_BLOCK:%.*]], label [[VECTOR_BODY]], !dbg !9, !llvm.loop !15
+; CHECK:       middle.block:
+; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[TMP2]], [[N_VEC]]
+; CHECK-NEXT:    br i1 [[CMP_N]], label [[FOR_END_LOOPEXIT:%.*]], label [[SCALAR_PH]], !dbg !9
+; CHECK:       scalar.ph:
+; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], [[MIDDLE_BLOCK]] ], [ 0, [[FOR_BODY_PREHEADER]] ], [ 0, [[VECTOR_MEMCHECK]] ]
+; CHECK-NEXT:    br label [[FOR_BODY:%.*]], !dbg !9
+; CHECK:       for.body:
+; CHECK-NEXT:    [[INDVARS_IV:%.*]] = phi i64 [ [[INDVARS_IV_NEXT:%.*]], [[FOR_BODY]] ], [ [[BC_RESUME_VAL]], [[SCALAR_PH]] ], !dbg !9
+; CHECK-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds float, float* [[B]], i64 [[INDVARS_IV]], !dbg !9
+; CHECK-NEXT:    [[TMP13:%.*]] = load float, float* [[ARRAYIDX]], align 4, !dbg !9
+; CHECK-NEXT:    [[MUL:%.*]] = fmul float [[TMP13]], 3.000000e+00, !dbg !9
+; CHECK-NEXT:    [[ARRAYIDX2:%.*]] = getelementptr inbounds float, float* [[A]], i64 [[INDVARS_IV]], !dbg !9
+; CHECK-NEXT:    store float [[MUL]], float* [[ARRAYIDX2]], align 4, !dbg !9
+; CHECK-NEXT:    [[INDVARS_IV_NEXT]] = add i64 [[INDVARS_IV]], 1, !dbg !9
+; CHECK-NEXT:    [[LFTR_WIDEIV:%.*]] = trunc i64 [[INDVARS_IV_NEXT]] to i32, !dbg !9
+; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp eq i32 [[LFTR_WIDEIV]], [[N]], !dbg !9
+; CHECK-NEXT:    br i1 [[EXITCOND]], label [[FOR_END_LOOPEXIT]], label [[FOR_BODY]], !dbg !9, !llvm.loop !17
+; CHECK:       for.end.loopexit:
+; CHECK-NEXT:    br label [[FOR_END]], !dbg !18
+; CHECK:       for.end:
+; CHECK-NEXT:    ret i32 undef, !dbg !18
+;
+entry:
+  %cmp6 = icmp sgt i32 %n, 0, !dbg !6
+  br i1 %cmp6, label %for.body, label %for.end, !dbg !6
+
+for.body:                                         ; preds = %entry, %for.body
+  %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %entry ], !dbg !7
+  %arrayidx = getelementptr inbounds float, float* %b, i64 %indvars.iv, !dbg !7
+  %0 = load float, float* %arrayidx, align 4, !dbg !7
+  %mul = fmul float %0, 3.000000e+00, !dbg !7
+  %arrayidx2 = getelementptr inbounds float, float* %a, i64 %indvars.iv, !dbg !7
+  store float %mul, float* %arrayidx2, align 4, !dbg !7
+  %indvars.iv.next = add i64 %indvars.iv, 1, !dbg !7
+  %lftr.wideiv = trunc i64 %indvars.iv.next to i32, !dbg !7
+  %exitcond = icmp eq i32 %lftr.wideiv, %n, !dbg !7
+  br i1 %exitcond, label %for.end, label %for.body, !dbg !7
+
+for.end:                                          ; preds = %for.body, %entry
+  ret i32 undef, !dbg !8
+}
+
+; Make sure that we try to vectorize loops with a runtime check if the
+; dependency check fails.
+
+; CHECK-LABEL: test_runtime_check
+; CHECK:      <4 x float>
+define void @test_runtime_check(float* %a, float %b, i64 %offset, i64 %offset2, i64 %n) {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i64 [ 0, %entry ], [ %iv.next, %for.body ]
+  %ind.sum = add i64 %iv, %offset
+  %arr.idx = getelementptr inbounds float, float* %a, i64 %ind.sum
+  %l1 = load float, float* %arr.idx, align 4
+  %ind.sum2 = add i64 %iv, %offset2
+  %arr.idx2 = getelementptr inbounds float, float* %a, i64 %ind.sum2
+  %l2 = load float, float* %arr.idx2, align 4
+  %m = fmul fast float %b, %l2
+  %ad = fadd fast float %l1, %m
+  store float %ad, float* %arr.idx, align 4
+  %iv.next = add nuw nsw i64 %iv, 1
+  %exitcond = icmp eq i64 %iv.next, %n
+  br i1 %exitcond, label %loopexit, label %for.body
+
+loopexit:
+  ret void
+}
+
+; Check we do not generate runtime checks if we found a known dependence preventing
+; vectorization. In this case, it is a read of c[i-1] followed by a write of c[i].
+; The runtime checks would always fail.
+
+; void test_runtime_check2(float *a, float b, unsigned offset, unsigned offset2, unsigned n, float *c) {
+;   for (unsigned i = 1; i < n; i++) {
+;     a[i+o1] += a[i+o2] + b;
+;     c[i] = c[i-1] + b;
+;   }
+; }
+;
+; CHECK-LABEL: test_runtime_check2
+; CHECK-NOT:      <4 x float>
+define void @test_runtime_check2(float* %a, float %b, i64 %offset, i64 %offset2, i64 %n, float* %c) {
+entry:
+  br label %for.body
+
+for.body:
+  %iv = phi i64 [ 0, %entry ], [ %iv.next, %for.body ]
+  %ind.sum = add i64 %iv, %offset
+  %arr.idx = getelementptr inbounds float, float* %a, i64 %ind.sum
+  %l1 = load float, float* %arr.idx, align 4
+  %ind.sum2 = add i64 %iv, %offset2
+  %arr.idx2 = getelementptr inbounds float, float* %a, i64 %ind.sum2
+  %l2 = load float, float* %arr.idx2, align 4
+  %m = fmul fast float %b, %l2
+  %ad = fadd fast float %l1, %m
+  store float %ad, float* %arr.idx, align 4
+  %c.ind = add i64 %iv, -1
+  %c.idx = getelementptr inbounds float, float* %c, i64 %c.ind
+  %lc = load float, float* %c.idx, align 4
+  %vc = fadd float %lc, 1.0
+  %c.idx2 = getelementptr inbounds float, float* %c, i64 %iv
+  store float %vc, float* %c.idx2
+  %iv.next = add nuw nsw i64 %iv, 1
+  %exitcond = icmp eq i64 %iv.next, %n
+  br i1 %exitcond, label %loopexit, label %for.body
+
+loopexit:
+  ret void
+}
+
+; CHECK: !9 = !DILocation(line: 101, column: 1, scope: !{{.*}})
+
+!llvm.module.flags = !{!0, !1}
+!llvm.dbg.cu = !{!9}
+!0 = !{i32 2, !"Dwarf Version", i32 4}
+!1 = !{i32 2, !"Debug Info Version", i32 3}
+
+!2 = !{}
+!3 = !DISubroutineType(types: !2)
+!4 = !DIFile(filename: "test.cpp", directory: "/tmp")
+!5 = distinct !DISubprogram(name: "foo", scope: !4, file: !4, line: 99, type: !3, isLocal: false, isDefinition: true, scopeLine: 100, flags: DIFlagPrototyped, isOptimized: false, unit: !9, retainedNodes: !2)
+!6 = !DILocation(line: 100, column: 1, scope: !5)
+!7 = !DILocation(line: 101, column: 1, scope: !5)
+!8 = !DILocation(line: 102, column: 1, scope: !5)
+!9 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "clang",
+                             file: !10,
+                             isOptimized: true, flags: "-O2",
+                             splitDebugFilename: "abc.debug", emissionKind: 2)
+!10 = !DIFile(filename: "path/to/file", directory: "/path/to/dir")
+!11 = !{i32 2, !"Debug Info Version", i32 3}