[LoopIdiomRecognizePass] Options to disable part or the entire Loop Idiom Recognize Pass
Loop Idiom Recognize Pass (LIRP) attempts to transform loops with subscripted arrays
into memcpy/memset function calls. In some particular situation, this transformation
introduces negative impacts. For example: https://bugs.llvm.org/show_bug.cgi?id=47300
This patch will enable users to disable a particular part of the transformation, while
he/she can still enjoy the benefit brought about by the rest of LIRP. The default
behavior stays unchanged: no part of LIRP is disabled by default.
Reviewed By: etiotto (Ettore Tiotto)
Differential Revision: https://reviews.llvm.org/D86262
diff --git a/llvm/test/Transforms/LoopIdiom/disable-options.ll b/llvm/test/Transforms/LoopIdiom/disable-options.ll
new file mode 100644
index 0000000..0a19aeb
--- /dev/null
+++ b/llvm/test/Transforms/LoopIdiom/disable-options.ll
@@ -0,0 +1,167 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -basic-aa -loop-idiom < %s -S | FileCheck %s --check-prefix=DIS-NONE
+; RUN: opt -basic-aa -loop-idiom -disable-loop-idiom-all < %s -S | FileCheck %s --check-prefix=DIS-ALL
+; RUN: opt -basic-aa -loop-idiom -disable-loop-idiom-memcpy < %s -S | FileCheck %s --check-prefix=DIS-MEMCPY
+; RUN: opt -basic-aa -loop-idiom -disable-loop-idiom-memset < %s -S | FileCheck %s --check-prefix=DIS-MEMSET
+; RUN: opt -basic-aa -loop-idiom -disable-loop-idiom-memset -disable-loop-idiom-memcpy < %s -S | FileCheck %s --check-prefix=DIS-ALL
+; RUN: opt -passes="loop-idiom" -aa-pipeline=basic-aa < %s -S | FileCheck %s --check-prefix=DIS-NONE
+; RUN: opt -passes="loop-idiom" -aa-pipeline=basic-aa -disable-loop-idiom-all < %s -S | FileCheck %s --check-prefix=DIS-ALL
+; RUN: opt -passes="loop-idiom" -aa-pipeline=basic-aa -disable-loop-idiom-memcpy < %s -S | FileCheck %s --check-prefix=DIS-MEMCPY
+; RUN: opt -passes="loop-idiom" -aa-pipeline=basic-aa -disable-loop-idiom-memset < %s -S | FileCheck %s --check-prefix=DIS-MEMSET
+; RUN: opt -passes="loop-idiom" -aa-pipeline=basic-aa -disable-loop-idiom-memset -disable-loop-idiom-memcpy < %s -S | FileCheck %s --check-prefix=DIS-ALL
+
+define void @test-memcpy(i64 %Size) nounwind ssp {
+; DIS-NONE-LABEL: @test-memcpy(
+; DIS-NONE-NEXT: bb.nph:
+; DIS-NONE-NEXT: [[BASE:%.*]] = alloca i8, i32 10000, align 1
+; DIS-NONE-NEXT: [[DEST:%.*]] = alloca i8, i32 10000, align 1
+; DIS-NONE-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 1 [[DEST]], i8* align 1 [[BASE]], i64 [[SIZE:%.*]], i1 false)
+; DIS-NONE-NEXT: br label [[FOR_BODY:%.*]]
+; DIS-NONE: for.body:
+; DIS-NONE-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[BB_NPH:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[FOR_BODY]] ]
+; DIS-NONE-NEXT: [[I_0_014:%.*]] = getelementptr i8, i8* [[BASE]], i64 [[INDVAR]]
+; DIS-NONE-NEXT: [[DESTI:%.*]] = getelementptr i8, i8* [[DEST]], i64 [[INDVAR]]
+; DIS-NONE-NEXT: [[V:%.*]] = load i8, i8* [[I_0_014]], align 1
+; DIS-NONE-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1
+; DIS-NONE-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], [[SIZE]]
+; DIS-NONE-NEXT: br i1 [[EXITCOND]], label [[FOR_END:%.*]], label [[FOR_BODY]]
+; DIS-NONE: for.end:
+; DIS-NONE-NEXT: ret void
+;
+; DIS-ALL-LABEL: @test-memcpy(
+; DIS-ALL-NEXT: bb.nph:
+; DIS-ALL-NEXT: [[BASE:%.*]] = alloca i8, i32 10000, align 1
+; DIS-ALL-NEXT: [[DEST:%.*]] = alloca i8, i32 10000, align 1
+; DIS-ALL-NEXT: br label [[FOR_BODY:%.*]]
+; DIS-ALL: for.body:
+; DIS-ALL-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[BB_NPH:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[FOR_BODY]] ]
+; DIS-ALL-NEXT: [[I_0_014:%.*]] = getelementptr i8, i8* [[BASE]], i64 [[INDVAR]]
+; DIS-ALL-NEXT: [[DESTI:%.*]] = getelementptr i8, i8* [[DEST]], i64 [[INDVAR]]
+; DIS-ALL-NEXT: [[V:%.*]] = load i8, i8* [[I_0_014]], align 1
+; DIS-ALL-NEXT: store i8 [[V]], i8* [[DESTI]], align 1
+; DIS-ALL-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1
+; DIS-ALL-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], [[SIZE:%.*]]
+; DIS-ALL-NEXT: br i1 [[EXITCOND]], label [[FOR_END:%.*]], label [[FOR_BODY]]
+; DIS-ALL: for.end:
+; DIS-ALL-NEXT: ret void
+;
+; DIS-MEMCPY-LABEL: @test-memcpy(
+; DIS-MEMCPY-NEXT: bb.nph:
+; DIS-MEMCPY-NEXT: [[BASE:%.*]] = alloca i8, i32 10000, align 1
+; DIS-MEMCPY-NEXT: [[DEST:%.*]] = alloca i8, i32 10000, align 1
+; DIS-MEMCPY-NEXT: br label [[FOR_BODY:%.*]]
+; DIS-MEMCPY: for.body:
+; DIS-MEMCPY-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[BB_NPH:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[FOR_BODY]] ]
+; DIS-MEMCPY-NEXT: [[I_0_014:%.*]] = getelementptr i8, i8* [[BASE]], i64 [[INDVAR]]
+; DIS-MEMCPY-NEXT: [[DESTI:%.*]] = getelementptr i8, i8* [[DEST]], i64 [[INDVAR]]
+; DIS-MEMCPY-NEXT: [[V:%.*]] = load i8, i8* [[I_0_014]], align 1
+; DIS-MEMCPY-NEXT: store i8 [[V]], i8* [[DESTI]], align 1
+; DIS-MEMCPY-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1
+; DIS-MEMCPY-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], [[SIZE:%.*]]
+; DIS-MEMCPY-NEXT: br i1 [[EXITCOND]], label [[FOR_END:%.*]], label [[FOR_BODY]]
+; DIS-MEMCPY: for.end:
+; DIS-MEMCPY-NEXT: ret void
+;
+; DIS-MEMSET-LABEL: @test-memcpy(
+; DIS-MEMSET-NEXT: bb.nph:
+; DIS-MEMSET-NEXT: [[BASE:%.*]] = alloca i8, i32 10000, align 1
+; DIS-MEMSET-NEXT: [[DEST:%.*]] = alloca i8, i32 10000, align 1
+; DIS-MEMSET-NEXT: call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 1 [[DEST]], i8* align 1 [[BASE]], i64 [[SIZE:%.*]], i1 false)
+; DIS-MEMSET-NEXT: br label [[FOR_BODY:%.*]]
+; DIS-MEMSET: for.body:
+; DIS-MEMSET-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[BB_NPH:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[FOR_BODY]] ]
+; DIS-MEMSET-NEXT: [[I_0_014:%.*]] = getelementptr i8, i8* [[BASE]], i64 [[INDVAR]]
+; DIS-MEMSET-NEXT: [[DESTI:%.*]] = getelementptr i8, i8* [[DEST]], i64 [[INDVAR]]
+; DIS-MEMSET-NEXT: [[V:%.*]] = load i8, i8* [[I_0_014]], align 1
+; DIS-MEMSET-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1
+; DIS-MEMSET-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], [[SIZE]]
+; DIS-MEMSET-NEXT: br i1 [[EXITCOND]], label [[FOR_END:%.*]], label [[FOR_BODY]]
+; DIS-MEMSET: for.end:
+; DIS-MEMSET-NEXT: ret void
+;
+bb.nph:
+ %Base = alloca i8, i32 10000
+ %Dest = alloca i8, i32 10000
+ br label %for.body
+
+for.body: ; preds = %bb.nph, %for.body
+ %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body ]
+ %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
+ %DestI = getelementptr i8, i8* %Dest, i64 %indvar
+ %V = load i8, i8* %I.0.014, align 1
+ store i8 %V, i8* %DestI, align 1
+ %indvar.next = add i64 %indvar, 1
+ %exitcond = icmp eq i64 %indvar.next, %Size
+ br i1 %exitcond, label %for.end, label %for.body
+
+for.end: ; preds = %for.body, %entry
+ ret void
+}
+
+define void @test-memset(i8* %Base, i64 %Size) nounwind ssp {
+; CHECK-LABEL: @test-memset(
+; CHECK-NEXT: bb.nph:
+; CHECK-NEXT: call void @llvm.memset.p0i8.i64(i8* align 1 [[BASE:%.*]], i8 0, i64 [[SIZE:%.*]], i1 false)
+; CHECK-NEXT: br label [[FOR_BODY:%.*]]
+; CHECK: for.body:
+; CHECK-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[BB_NPH:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[FOR_BODY]] ]
+; CHECK-NEXT: [[I_0_014:%.*]] = getelementptr i8, i8* [[BASE]], i64 [[INDVAR]]
+; CHECK-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1
+; CHECK-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], [[SIZE]]
+; CHECK-NEXT: br i1 [[EXITCOND]], label [[FOR_END:%.*]], label [[FOR_BODY]]
+; CHECK: for.end:
+; CHECK-NEXT: ret void
+;
+; DIS-ALL-LABEL: @test-memset(
+; DIS-ALL-NEXT: bb.nph:
+; DIS-ALL-NEXT: br label [[FOR_BODY:%.*]]
+; DIS-ALL: for.body:
+; DIS-ALL-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[BB_NPH:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[FOR_BODY]] ]
+; DIS-ALL-NEXT: [[I_0_014:%.*]] = getelementptr i8, i8* [[BASE:%.*]], i64 [[INDVAR]]
+; DIS-ALL-NEXT: store i8 0, i8* [[I_0_014]], align 1
+; DIS-ALL-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1
+; DIS-ALL-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], [[SIZE:%.*]]
+; DIS-ALL-NEXT: br i1 [[EXITCOND]], label [[FOR_END:%.*]], label [[FOR_BODY]]
+; DIS-ALL: for.end:
+; DIS-ALL-NEXT: ret void
+;
+; DIS-MEMCPY-LABEL: @test-memset(
+; DIS-MEMCPY-NEXT: bb.nph:
+; DIS-MEMCPY-NEXT: call void @llvm.memset.p0i8.i64(i8* align 1 [[BASE:%.*]], i8 0, i64 [[SIZE:%.*]], i1 false)
+; DIS-MEMCPY-NEXT: br label [[FOR_BODY:%.*]]
+; DIS-MEMCPY: for.body:
+; DIS-MEMCPY-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[BB_NPH:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[FOR_BODY]] ]
+; DIS-MEMCPY-NEXT: [[I_0_014:%.*]] = getelementptr i8, i8* [[BASE]], i64 [[INDVAR]]
+; DIS-MEMCPY-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1
+; DIS-MEMCPY-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], [[SIZE]]
+; DIS-MEMCPY-NEXT: br i1 [[EXITCOND]], label [[FOR_END:%.*]], label [[FOR_BODY]]
+; DIS-MEMCPY: for.end:
+; DIS-MEMCPY-NEXT: ret void
+;
+; DIS-MEMSET-LABEL: @test-memset(
+; DIS-MEMSET-NEXT: bb.nph:
+; DIS-MEMSET-NEXT: br label [[FOR_BODY:%.*]]
+; DIS-MEMSET: for.body:
+; DIS-MEMSET-NEXT: [[INDVAR:%.*]] = phi i64 [ 0, [[BB_NPH:%.*]] ], [ [[INDVAR_NEXT:%.*]], [[FOR_BODY]] ]
+; DIS-MEMSET-NEXT: [[I_0_014:%.*]] = getelementptr i8, i8* [[BASE:%.*]], i64 [[INDVAR]]
+; DIS-MEMSET-NEXT: store i8 0, i8* [[I_0_014]], align 1
+; DIS-MEMSET-NEXT: [[INDVAR_NEXT]] = add i64 [[INDVAR]], 1
+; DIS-MEMSET-NEXT: [[EXITCOND:%.*]] = icmp eq i64 [[INDVAR_NEXT]], [[SIZE:%.*]]
+; DIS-MEMSET-NEXT: br i1 [[EXITCOND]], label [[FOR_END:%.*]], label [[FOR_BODY]]
+; DIS-MEMSET: for.end:
+; DIS-MEMSET-NEXT: ret void
+;
+bb.nph: ; preds = %entry
+ br label %for.body
+
+for.body: ; preds = %bb.nph, %for.body
+ %indvar = phi i64 [ 0, %bb.nph ], [ %indvar.next, %for.body ]
+ %I.0.014 = getelementptr i8, i8* %Base, i64 %indvar
+ store i8 0, i8* %I.0.014, align 1
+ %indvar.next = add i64 %indvar, 1
+ %exitcond = icmp eq i64 %indvar.next, %Size
+ br i1 %exitcond, label %for.end, label %for.body
+
+for.end: ; preds = %for.body, %entry
+ ret void
+}