[LV] Pre-committing tests for changing loop interleaving count computation #70272
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@llvm/pr-subscribers-llvm-transforms Author: Nilanjana Basu (nilanjana87) ChangesAdded tests for evaluating changes to loop interleaving count computation and for removing loop interleaving threshold. Full diff: https://github.com/llvm/llvm-project/pull/70272.diff 2 Files Affected:
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/interleave_count.ll b/llvm/test/Transforms/LoopVectorize/AArch64/interleave_count.ll
new file mode 100644
index 000000000000000..74fd2f44fce0109
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/interleave_count.ll
@@ -0,0 +1,106 @@
+; RUN: opt < %s -force-vector-width=64 -O3 -S -pass-remarks=loop-vectorize 2>&1 | FileCheck %s
+
+target triple = "aarch64-linux-gnu"
+
+%pair = type { i8, i8 }
+
+; For a loop with known trip count of 128, when we force VF 64, it should use
+; IC 2, since there is no remainder loop needed when the vector loop runs.
+; CHECK: remark: <unknown>:0:0: vectorized loop (vectorization width: 64, interleaved count: 2)
+define void @loop_with_tc_128(ptr %p, ptr %q) {
+entry:
+ br label %for.body
+
+for.body:
+ %i = phi i64 [ 0, %entry ], [ %i.next, %for.body ]
+ %tmp0 = getelementptr %pair, ptr %p, i64 %i, i32 0
+ %tmp1 = load i8, ptr %tmp0, align 1
+ %tmp2 = getelementptr %pair, ptr %p, i64 %i, i32 1
+ %tmp3 = load i8, ptr %tmp2, align 1
+ %add = add i8 %tmp1, %tmp3
+ %qi = getelementptr i8, ptr %q, i64 %i
+ store i8 %add, ptr %qi, align 1
+ %i.next = add nuw nsw i64 %i, 1
+ %cond = icmp eq i64 %i.next, 128
+ br i1 %cond, label %for.end, label %for.body
+
+for.end:
+ ret void
+}
+
+; For a loop with known trip count of 129, when we force VF 64, it should use
+; IC 1, since there may be a remainder loop that needs to run after the vector loop.
+; CHECK: remark: <unknown>:0:0: vectorized loop (vectorization width: 64, interleaved count: 2)
+define void @loop_with_tc_129(ptr %p, ptr %q) {
+entry:
+ br label %for.body
+
+for.body:
+ %i = phi i64 [ 0, %entry ], [ %i.next, %for.body ]
+ %tmp0 = getelementptr %pair, ptr %p, i64 %i, i32 0
+ %tmp1 = load i8, ptr %tmp0, align 1
+ %tmp2 = getelementptr %pair, ptr %p, i64 %i, i32 1
+ %tmp3 = load i8, ptr %tmp2, align 1
+ %add = add i8 %tmp1, %tmp3
+ %qi = getelementptr i8, ptr %q, i64 %i
+ store i8 %add, ptr %qi, align 1
+ %i.next = add nuw nsw i64 %i, 1
+ %cond = icmp eq i64 %i.next, 129
+ br i1 %cond, label %for.end, label %for.body
+
+for.end:
+ ret void
+}
+
+; For a loop with unknown trip count but a profile showing an approx TC estimate of 128,
+; when we force VF 64, it should use IC 2, since chances are high that the remainder loop
+; won't need to run
+; CHECK: remark: <unknown>:0:0: vectorized loop (vectorization width: 64, interleaved count: 2)
+define void @loop_with_profile_tc_128(ptr %p, ptr %q, i64 %n) {
+entry:
+ br label %for.body
+
+for.body:
+ %i = phi i64 [ 0, %entry ], [ %i.next, %for.body ]
+ %tmp0 = getelementptr %pair, ptr %p, i64 %i, i32 0
+ %tmp1 = load i8, ptr %tmp0, align 1
+ %tmp2 = getelementptr %pair, ptr %p, i64 %i, i32 1
+ %tmp3 = load i8, ptr %tmp2, align 1
+ %add = add i8 %tmp1, %tmp3
+ %qi = getelementptr i8, ptr %q, i64 %i
+ store i8 %add, ptr %qi, align 1
+ %i.next = add nuw nsw i64 %i, 1
+ %cond = icmp eq i64 %i.next, %n
+ br i1 %cond, label %for.end, label %for.body, !prof !0
+
+for.end:
+ ret void
+}
+
+; For a loop with unknown trip count but a profile showing an approx TC estimate of 129,
+; when we force VF 64, it should use IC 1, since chances are high that the remainder loop
+; will need to run
+; CHECK: remark: <unknown>:0:0: vectorized loop (vectorization width: 64, interleaved count: 2)
+define void @loop_with_profile_tc_129(ptr %p, ptr %q, i64 %n) {
+entry:
+ br label %for.body
+
+for.body:
+ %i = phi i64 [ 0, %entry ], [ %i.next, %for.body ]
+ %tmp0 = getelementptr %pair, ptr %p, i64 %i, i32 0
+ %tmp1 = load i8, ptr %tmp0, align 1
+ %tmp2 = getelementptr %pair, ptr %p, i64 %i, i32 1
+ %tmp3 = load i8, ptr %tmp2, align 1
+ %add = add i8 %tmp1, %tmp3
+ %qi = getelementptr i8, ptr %q, i64 %i
+ store i8 %add, ptr %qi, align 1
+ %i.next = add nuw nsw i64 %i, 1
+ %cond = icmp eq i64 %i.next, %n
+ br i1 %cond, label %for.end, label %for.body, !prof !1
+
+for.end:
+ ret void
+}
+
+!0 = !{!"branch_weights", i32 1, i32 127}
+!1 = !{!"branch_weights", i32 1, i32 128}
diff --git a/llvm/test/Transforms/LoopVectorize/X86/unroll-small-loops.ll b/llvm/test/Transforms/LoopVectorize/X86/unroll-small-loops.ll
index 290be569bc12524..6b71cfef06be149 100644
--- a/llvm/test/Transforms/LoopVectorize/X86/unroll-small-loops.ll
+++ b/llvm/test/Transforms/LoopVectorize/X86/unroll-small-loops.ll
@@ -8,20 +8,20 @@ target triple = "x86_64-apple-macosx10.8.0"
; We don't unroll this loop because it has a small constant trip count.
;
-; CHECK-VECTOR-LABEL: @foo(
+; CHECK-VECTOR-LABEL: @foo_trip_count_8(
; CHECK-VECTOR: load <4 x i32>
; CHECK-VECTOR-NOT: load <4 x i32>
; CHECK-VECTOR: store <4 x i32>
; CHECK-VECTOR-NOT: store <4 x i32>
; CHECK-VECTOR: ret
;
-; CHECK-SCALAR-LABEL: @foo(
+; CHECK-SCALAR-LABEL: @foo_trip_count_8(
; CHECK-SCALAR: load i32, ptr
; CHECK-SCALAR-NOT: load i32, ptr
; CHECK-SCALAR: store i32
; CHECK-SCALAR-NOT: store i32
; CHECK-SCALAR: ret
-define i32 @foo(ptr nocapture %A) nounwind uwtable ssp {
+define i32 @foo_trip_count_8(ptr nocapture %A) nounwind uwtable ssp {
br label %1
; <label>:1 ; preds = %1, %0
@@ -32,7 +32,193 @@ define i32 @foo(ptr nocapture %A) nounwind uwtable ssp {
store i32 %4, ptr %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, 100
+ %exitcond = icmp eq i32 %lftr.wideiv, 8
+ br i1 %exitcond, label %5, label %1
+
+; <label>:5 ; preds = %1
+ ret i32 undef
+}
+
+; CHECK-VECTOR-LABEL: @foo_trip_count_16(
+; CHECK-VECTOR: load <4 x i32>
+; CHECK-VECTOR-NOT: load <4 x i32>
+; CHECK-VECTOR: store <4 x i32>
+; CHECK-VECTOR-NOT: store <4 x i32>
+; CHECK-VECTOR: ret
+;
+; CHECK-SCALAR-LABEL: @foo_trip_count_16(
+; CHECK-SCALAR: load i32, ptr
+; CHECK-SCALAR-NOT: load i32, ptr
+; CHECK-SCALAR: store i32
+; CHECK-SCALAR-NOT: store i32
+; CHECK-SCALAR: ret
+define i32 @foo_trip_count_16(ptr nocapture %A) nounwind uwtable ssp {
+ br label %1
+
+; <label>:1 ; preds = %1, %0
+ %indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %1 ]
+ %2 = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
+ %3 = load i32, ptr %2, align 4
+ %4 = add nsw i32 %3, 6
+ store i32 %4, ptr %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, 16
+ br i1 %exitcond, label %5, label %1
+
+; <label>:5 ; preds = %1
+ ret i32 undef
+}
+
+; CHECK-VECTOR-LABEL: @foo_trip_count_17(
+; CHECK-VECTOR: load <4 x i32>
+; CHECK-VECTOR-NOT: load <4 x i32>
+; CHECK-VECTOR: store <4 x i32>
+; CHECK-VECTOR-NOT: store <4 x i32>
+; CHECK-VECTOR: ret
+;
+; CHECK-SCALAR-LABEL: @foo_trip_count_17(
+; CHECK-SCALAR: load i32, ptr
+; CHECK-SCALAR-NOT: load i32, ptr
+; CHECK-SCALAR: store i32
+; CHECK-SCALAR-NOT: store i32
+; CHECK-SCALAR: ret
+define i32 @foo_trip_count_17(ptr nocapture %A) nounwind uwtable ssp {
+ br label %1
+
+; <label>:1 ; preds = %1, %0
+ %indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %1 ]
+ %2 = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
+ %3 = load i32, ptr %2, align 4
+ %4 = add nsw i32 %3, 6
+ store i32 %4, ptr %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, 17
+ br i1 %exitcond, label %5, label %1
+
+; <label>:5 ; preds = %1
+ ret i32 undef
+}
+
+; CHECK-VECTOR-LABEL: @foo_trip_count_24(
+; CHECK-VECTOR: load <4 x i32>
+; CHECK-VECTOR-NOT: load <4 x i32>
+; CHECK-VECTOR: store <4 x i32>
+; CHECK-VECTOR-NOT: store <4 x i32>
+; CHECK-VECTOR: ret
+;
+; CHECK-SCALAR-LABEL: @foo_trip_count_24(
+; CHECK-SCALAR: load i32, ptr
+; CHECK-SCALAR-NOT: load i32, ptr
+; CHECK-SCALAR: store i32
+; CHECK-SCALAR-NOT: store i32
+; CHECK-SCALAR: ret
+define i32 @foo_trip_count_24(ptr nocapture %A) nounwind uwtable ssp {
+ br label %1
+
+; <label>:1 ; preds = %1, %0
+ %indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %1 ]
+ %2 = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
+ %3 = load i32, ptr %2, align 4
+ %4 = add nsw i32 %3, 6
+ store i32 %4, ptr %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, 24
+ br i1 %exitcond, label %5, label %1
+
+; <label>:5 ; preds = %1
+ ret i32 undef
+}
+
+; CHECK-VECTOR-LABEL: @foo_trip_count_25(
+; CHECK-VECTOR: load <4 x i32>
+; CHECK-VECTOR-NOT: load <4 x i32>
+; CHECK-VECTOR: store <4 x i32>
+; CHECK-VECTOR-NOT: store <4 x i32>
+; CHECK-VECTOR: ret
+;
+; CHECK-SCALAR-LABEL: @foo_trip_count_25(
+; CHECK-SCALAR: load i32, ptr
+; CHECK-SCALAR-NOT: load i32, ptr
+; CHECK-SCALAR: store i32
+; CHECK-SCALAR-NOT: store i32
+; CHECK-SCALAR: ret
+define i32 @foo_trip_count_25(ptr nocapture %A) nounwind uwtable ssp {
+ br label %1
+
+; <label>:1 ; preds = %1, %0
+ %indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %1 ]
+ %2 = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
+ %3 = load i32, ptr %2, align 4
+ %4 = add nsw i32 %3, 6
+ store i32 %4, ptr %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, 25
+ br i1 %exitcond, label %5, label %1
+
+; <label>:5 ; preds = %1
+ ret i32 undef
+}
+
+; CHECK-VECTOR-LABEL: @foo_trip_count_33(
+; CHECK-VECTOR: load <4 x i32>
+; CHECK-VECTOR-NOT: load <4 x i32>
+; CHECK-VECTOR: store <4 x i32>
+; CHECK-VECTOR-NOT: store <4 x i32>
+; CHECK-VECTOR: ret
+;
+; CHECK-SCALAR-LABEL: @foo_trip_count_33(
+; CHECK-SCALAR: load i32, ptr
+; CHECK-SCALAR-NOT: load i32, ptr
+; CHECK-SCALAR: store i32
+; CHECK-SCALAR-NOT: store i32
+; CHECK-SCALAR: ret
+define i32 @foo_trip_count_33(ptr nocapture %A) nounwind uwtable ssp {
+ br label %1
+
+; <label>:1 ; preds = %1, %0
+ %indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %1 ]
+ %2 = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
+ %3 = load i32, ptr %2, align 4
+ %4 = add nsw i32 %3, 6
+ store i32 %4, ptr %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, 33
+ br i1 %exitcond, label %5, label %1
+
+; <label>:5 ; preds = %1
+ ret i32 undef
+}
+
+; CHECK-VECTOR-LABEL: @foo_trip_count_101(
+; CHECK-VECTOR: load <4 x i32>
+; CHECK-VECTOR-NOT: load <4 x i32>
+; CHECK-VECTOR: store <4 x i32>
+; CHECK-VECTOR-NOT: store <4 x i32>
+; CHECK-VECTOR: ret
+;
+; CHECK-SCALAR-LABEL: @foo_trip_count_101(
+; CHECK-SCALAR: load i32, ptr
+; CHECK-SCALAR-NOT: load i32, ptr
+; CHECK-SCALAR: store i32
+; CHECK-SCALAR-NOT: store i32
+; CHECK-SCALAR: ret
+define i32 @foo_trip_count_101(ptr nocapture %A) nounwind uwtable ssp {
+ br label %1
+
+; <label>:1 ; preds = %1, %0
+ %indvars.iv = phi i64 [ 0, %0 ], [ %indvars.iv.next, %1 ]
+ %2 = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
+ %3 = load i32, ptr %2, align 4
+ %4 = add nsw i32 %3, 6
+ store i32 %4, ptr %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, 101
br i1 %exitcond, label %5, label %1
; <label>:5 ; preds = %1
|
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Since this patch is the first part of a two-part patch for changing loop interleaving count computation, followed by removing loop interleaving threshold, these tests remain unchanged for the current (first) patch but will be modified for the second patch. The original PR for these tests is in llvm#70272.
fhahn
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Oct 26, 2023
- replaced -O3 in tests with -p loop-vectorize - added "TODO" in comments for tests that are meant to change after the subsequent patch - used named labels for basic blocks
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fhahn
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…n change in subsequent patches without the need to force VF
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sr-tream
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…ation (llvm#70272) Added tests for evaluating changes to loop interleaving count computation and for removing loop interleaving threshold in subsequent patches.
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…ation (llvm#70272) Added tests for evaluating changes to loop interleaving count computation and for removing loop interleaving threshold in subsequent patches.
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[LV] Change loops' interleave count computation A set of microbenchmarks in llvm-test-suite (llvm/llvm-test-suite#56), when tested on a AArch64 platform, demonstrates that loop interleaving is beneficial when the vector loop runs at least twice or when the epilogue loop trip count (TC) is minimal. Therefore, we choose interleaving count (IC) between TC/VF & TC/2*VF (VF = vectorization factor), such that remainder TC for the epilogue loop is minimum while the IC is maximum in case the remainder TC is same for both. The initial tests for this change were submitted in PRs: #70272 and #74689.
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…ation (llvm#70272) Added tests for evaluating changes to loop interleaving count computation and for removing loop interleaving threshold in subsequent patches.
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[LV] Change loops' interleave count computation A set of microbenchmarks in llvm-test-suite (llvm/llvm-test-suite#56), when tested on a AArch64 platform, demonstrates that loop interleaving is beneficial when the vector loop runs at least twice or when the epilogue loop trip count (TC) is minimal. Therefore, we choose interleaving count (IC) between TC/VF & TC/2*VF (VF = vectorization factor), such that remainder TC for the epilogue loop is minimum while the IC is maximum in case the remainder TC is same for both. The initial tests for this change were submitted in PRs: llvm#70272 and llvm#74689.
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Added tests for evaluating changes to loop interleaving count computation and for removing loop interleaving threshold.