Revert "Temporarily Revert "Add basic loop fusion pass.""

The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552

8 files changed, 522 insertions, 0 deletions

diff --git a/llvm/test/Transforms/GCOVProfiling/function-numbering.ll b/llvm/test/Transforms/GCOVProfiling/function-numbering.ll
new file mode 100644
index 00000000000..f9a95fd1c25
--- /dev/null
+++ b/llvm/test/Transforms/GCOVProfiling/function-numbering.ll
@@ -0,0 +1,123 @@
+; Test that GCOV instrumentation numbers functions correctly when some
+; functions aren't emitted.
+
+; Inject metadata to set the .gcno file location
+; RUN: rm -rf %t && mkdir -p %t
+; RUN: echo '!14 = !{!"%/t/function-numbering.ll", !0}' > %t/1
+; RUN: cat %s %t/1 > %t/2
+
+; RUN: opt -insert-gcov-profiling -S < %t/2 | FileCheck --check-prefix GCDA %s
+; RUN: llvm-cov gcov -n -dump %t/function-numbering.gcno 2>&1 | FileCheck --check-prefix GCNO %s
+; RUNN: rm %t/function-numbering.gcno
+
+; RUN: opt -passes=insert-gcov-profiling -S < %t/2 | FileCheck --check-prefix GCDA %s
+; RUN: llvm-cov gcov -n -dump %t/function-numbering.gcno 2>&1 | FileCheck --check-prefix GCNO %s
+
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.10.0"
+
+; GCDA: @[[FOO:[0-9]+]] = private unnamed_addr constant [4 x i8] c"foo\00"
+; GCDA-NOT: @{{[0-9]+}} = private unnamed_addr constant .* c"bar\00"
+; GCDA: @[[BAZ:[0-9]+]] = private unnamed_addr constant [4 x i8] c"baz\00"
+; GCDA: @__llvm_internal_gcov_emit_function_args.0 = internal unnamed_addr constant
+; GCDA-SAME: { i32 0, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @[[FOO]]
+; GCDA-SAME: { i32 1, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @[[BAZ]]
+;
+; GCDA-LABEL: define internal void @__llvm_gcov_writeout() {{.*}} {
+; GCDA-NEXT:  entry:
+; GCDA-NEXT:    br label %[[FILE_LOOP_HEADER:.*]]
+;
+; GCDA:       [[FILE_LOOP_HEADER]]:
+; GCDA-NEXT:    %[[IV:.*]] = phi i32 [ 0, %entry ], [ %[[NEXT_IV:.*]], %[[FILE_LOOP_LATCH:.*]] ]
+; GCDA-NEXT:    %[[FILE_INFO:.*]] = getelementptr inbounds {{.*}}, {{.*}}* @__llvm_internal_gcov_emit_file_info, i32 0, i32 %[[IV]]
+; GCDA-NEXT:    %[[START_FILE_ARGS:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[FILE_INFO]], i32 0, i32 0
+; GCDA-NEXT:    %[[START_FILE_ARG_0_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[START_FILE_ARGS]], i32 0, i32 0
+; GCDA-NEXT:    %[[START_FILE_ARG_0:.*]] = load i8*, i8** %[[START_FILE_ARG_0_PTR]]
+; GCDA-NEXT:    %[[START_FILE_ARG_1_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[START_FILE_ARGS]], i32 0, i32 1
+; GCDA-NEXT:    %[[START_FILE_ARG_1:.*]] = load i8*, i8** %[[START_FILE_ARG_1_PTR]]
+; GCDA-NEXT:    %[[START_FILE_ARG_2_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[START_FILE_ARGS]], i32 0, i32 2
+; GCDA-NEXT:    %[[START_FILE_ARG_2:.*]] = load i32, i32* %[[START_FILE_ARG_2_PTR]]
+; GCDA-NEXT:    call void @llvm_gcda_start_file(i8* %[[START_FILE_ARG_0]], i8* %[[START_FILE_ARG_1]], i32 %[[START_FILE_ARG_2]])
+; GCDA-NEXT:    %[[NUM_COUNTERS_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[FILE_INFO]], i32 0, i32 1
+; GCDA-NEXT:    %[[NUM_COUNTERS:.*]] = load i32, i32* %[[NUM_COUNTERS_PTR]]
+; GCDA-NEXT:    %[[EMIT_FUN_ARGS_ARRAY_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[FILE_INFO]], i32 0, i32 2
+; GCDA-NEXT:    %[[EMIT_FUN_ARGS_ARRAY:.*]] = load {{.*}}*, {{.*}}** %[[EMIT_FUN_ARGS_ARRAY_PTR]]
+; GCDA-NEXT:    %[[EMIT_ARCS_ARGS_ARRAY_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[FILE_INFO]], i32 0, i32 3
+; GCDA-NEXT:    %[[EMIT_ARCS_ARGS_ARRAY:.*]] = load {{.*}}*, {{.*}}** %[[EMIT_ARCS_ARGS_ARRAY_PTR]]
+; GCDA-NEXT:    %[[ENTER_COUNTER_LOOP_COND:.*]] = icmp slt i32 0, %[[NUM_COUNTERS]]
+; GCDA-NEXT:    br i1 %[[ENTER_COUNTER_LOOP_COND]], label %[[COUNTER_LOOP:.*]], label %[[FILE_LOOP_LATCH]]
+;
+; GCDA:       [[COUNTER_LOOP]]:
+; GCDA-NEXT:    %[[JV:.*]] = phi i32 [ 0, %[[FILE_LOOP_HEADER]] ], [ %[[NEXT_JV:.*]], %[[COUNTER_LOOP]] ]
+; GCDA-NEXT:    %[[EMIT_FUN_ARGS:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_FUN_ARGS_ARRAY]], i32 %[[JV]]
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_0_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_FUN_ARGS]], i32 0, i32 0
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_0:.*]] = load i32, i32* %[[EMIT_FUN_ARG_0_PTR]]
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_1_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_FUN_ARGS]], i32 0, i32 1
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_1:.*]] = load i8*, i8** %[[EMIT_FUN_ARG_1_PTR]]
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_2_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_FUN_ARGS]], i32 0, i32 2
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_2:.*]] = load i32, i32* %[[EMIT_FUN_ARG_2_PTR]]
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_3_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_FUN_ARGS]], i32 0, i32 3
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_3:.*]] = load i8, i8* %[[EMIT_FUN_ARG_3_PTR]]
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_4_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_FUN_ARGS]], i32 0, i32 4
+; GCDA-NEXT:    %[[EMIT_FUN_ARG_4:.*]] = load i32, i32* %[[EMIT_FUN_ARG_4_PTR]]
+; GCDA-NEXT:    call void @llvm_gcda_emit_function(i32 %[[EMIT_FUN_ARG_0]],
+; GCDA-SAME:                                       i8* %[[EMIT_FUN_ARG_1]],
+; GCDA-SAME:                                       i32 %[[EMIT_FUN_ARG_2]],
+; GCDA-SAME:                                       i8 %[[EMIT_FUN_ARG_3]],
+; GCDA-SAME:                                       i32 %[[EMIT_FUN_ARG_4]])
+; GCDA-NEXT:    %[[EMIT_ARCS_ARGS:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_ARCS_ARGS_ARRAY]], i32 %[[JV]]
+; GCDA-NEXT:    %[[EMIT_ARCS_ARG_0_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_ARCS_ARGS]], i32 0, i32 0
+; GCDA-NEXT:    %[[EMIT_ARCS_ARG_0:.*]] = load i32, i32* %[[EMIT_ARCS_ARG_0_PTR]]
+; GCDA-NEXT:    %[[EMIT_ARCS_ARG_1_PTR:.*]] = getelementptr inbounds {{.*}}, {{.*}}* %[[EMIT_ARCS_ARGS]], i32 0, i32 1
+; GCDA-NEXT:    %[[EMIT_ARCS_ARG_1:.*]] = load i64*, i64** %[[EMIT_ARCS_ARG_1_PTR]]
+; GCDA-NEXT:    call void @llvm_gcda_emit_arcs(i32 %[[EMIT_ARCS_ARG_0]],
+; GCDA-SAME:                                   i64* %[[EMIT_ARCS_ARG_1]])
+; GCDA-NEXT:    %[[NEXT_JV]] = add i32 %[[JV]], 1
+; GCDA-NEXT:    %[[COUNTER_LOOP_COND:.*]] = icmp slt i32 %[[NEXT_JV]], %[[NUM_COUNTERS]]
+; GCDA-NEXT:    br i1 %[[COUNTER_LOOP_COND]], label %[[COUNTER_LOOP]], label %[[FILE_LOOP_LATCH]]
+;
+; GCDA:       [[FILE_LOOP_LATCH]]:
+; GCDA-NEXT:    call void @llvm_gcda_summary_info()
+; GCDA-NEXT:    call void @llvm_gcda_end_file()
+; GCDA-NEXT:    %[[NEXT_IV]] = add i32 %[[IV]], 1
+; GCDA-NEXT:    %[[FILE_LOOP_COND:.*]] = icmp slt i32 %[[NEXT_IV]], 1
+; GCDA-NEXT:    br i1 %[[FILE_LOOP_COND]], label %[[FILE_LOOP_HEADER]], label %[[EXIT:.*]]
+;
+; GCDA:       [[EXIT]]:
+; GCDA-NEXT:    ret void
+
+; GCNO: == foo (0) @
+; GCNO-NOT: == bar ({{[0-9]+}}) @
+; GCNO: == baz (1) @
+
+define void @foo() !dbg !4 {
+  ret void, !dbg !12
+}
+
+define void @bar() !dbg !7 {
+  ; This function is referenced by the debug info, but no lines have locations.
+  ret void
+}
+
+define void @baz() !dbg !8 {
+  ret void, !dbg !13
+}
+
+!llvm.gcov = !{!14}
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!9, !10}
+!llvm.ident = !{!11}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "clang version 3.6.0 ", isOptimized: false, emissionKind: LineTablesOnly, file: !1, enums: !2, retainedTypes: !2, globals: !2, imports: !2)
+!1 = !DIFile(filename: ".../llvm/test/Transforms/GCOVProfiling/function-numbering.ll", directory: "")
+!2 = !{}
+!4 = distinct !DISubprogram(name: "foo", line: 1, isLocal: false, isDefinition: true, isOptimized: false, unit: !0, scopeLine: 1, file: !1, scope: !5, type: !6, retainedNodes: !2)
+!5 = !DIFile(filename: ".../llvm/test/Transforms/GCOVProfiling/function-numbering.ll", directory: "")
+!6 = !DISubroutineType(types: !2)
+!7 = distinct !DISubprogram(name: "bar", line: 2, isLocal: false, isDefinition: true, isOptimized: false, unit: !0, scopeLine: 2, file: !1, scope: !5, type: !6, retainedNodes: !2)
+!8 = distinct !DISubprogram(name: "baz", line: 3, isLocal: false, isDefinition: true, isOptimized: false, unit: !0, scopeLine: 3, file: !1, scope: !5, type: !6, retainedNodes: !2)
+!9 = !{i32 2, !"Dwarf Version", i32 2}
+!10 = !{i32 2, !"Debug Info Version", i32 3}
+!11 = !{!"clang version 3.6.0 "}
+!12 = !DILocation(line: 1, column: 13, scope: !4)
+!13 = !DILocation(line: 3, column: 13, scope: !8)
diff --git a/llvm/test/Transforms/GCOVProfiling/global-ctor.ll b/llvm/test/Transforms/GCOVProfiling/global-ctor.ll
new file mode 100644
index 00000000000..4f9d2e89457
--- /dev/null
+++ b/llvm/test/Transforms/GCOVProfiling/global-ctor.ll
@@ -0,0 +1,60 @@
+; RUN: rm -rf %t && mkdir -p %t
+; RUN: echo '!16 = !{!"%/t/global-ctor.ll", !0}' > %t/1
+; RUN: cat %s %t/1 > %t/2
+; RUN: opt -insert-gcov-profiling -disable-output < %t/2
+; RUN: not grep '_GLOBAL__sub_I_global-ctor' %t/global-ctor.gcno
+; RUN: rm %t/global-ctor.gcno
+
+; RUN: opt -passes=insert-gcov-profiling -disable-output < %t/2
+; RUN: not grep '_GLOBAL__sub_I_global-ctor' %t/global-ctor.gcno
+; RUN: rm %t/global-ctor.gcno
+
+@x = global i32 0, align 4
+@llvm.global_ctors = appending global [1 x { i32, void ()*, i8* }] [{ i32, void ()*, i8* } { i32 65535, void ()* @_GLOBAL__sub_I_global-ctor.ll, i8* null }]
+
+; Function Attrs: nounwind
+define internal void @__cxx_global_var_init() #0 section ".text.startup" !dbg !4 {
+entry:
+  br label %0
+
+; <label>:0                                       ; preds = %entry
+  %call = call i32 @_Z1fv(), !dbg !13
+  store i32 %call, i32* @x, align 4, !dbg !13
+  ret void, !dbg !13
+}
+
+declare i32 @_Z1fv() #1
+
+; Function Attrs: nounwind
+define internal void @_GLOBAL__sub_I_global-ctor.ll() #0 section ".text.startup" {
+entry:
+  br label %0
+
+; <label>:0                                       ; preds = %entry
+  call void @__cxx_global_var_init(), !dbg !14
+  ret void, !dbg !14
+}
+
+attributes #0 = { nounwind }
+attributes #1 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!10, !11}
+!llvm.gcov = !{!16}
+!llvm.ident = !{!12}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.5.0 (trunk 210217)", isOptimized: false, emissionKind: LineTablesOnly, file: !1, enums: !2, retainedTypes: !2, globals: !2, imports: !2)
+!1 = !DIFile(filename: "<stdin>", directory: "/home/nlewycky")
+!2 = !{}
+!4 = distinct !DISubprogram(name: "__cxx_global_var_init", line: 2, isLocal: true, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 2, file: !5, scope: !6, type: !7, retainedNodes: !2)
+!5 = !DIFile(filename: "global-ctor.ll", directory: "/home/nlewycky")
+!6 = !DIFile(filename: "global-ctor.ll", directory: "/home/nlewycky")
+!7 = !DISubroutineType(types: !2)
+!8 = distinct !DISubprogram(name: "", linkageName: "_GLOBAL__sub_I_global-ctor.ll", isLocal: true, isDefinition: true, virtualIndex: 6, flags: DIFlagArtificial, isOptimized: false, unit: !0, file: !1, scope: !9, type: !7, retainedNodes: !2)
+!9 = !DIFile(filename: "<stdin>", directory: "/home/nlewycky")
+!10 = !{i32 2, !"Dwarf Version", i32 4}
+!11 = !{i32 2, !"Debug Info Version", i32 3}
+!12 = !{!"clang version 3.5.0 (trunk 210217)"}
+!13 = !DILocation(line: 2, scope: !4)
+!14 = !DILocation(line: 0, scope: !15)
+!15 = !DILexicalBlockFile(discriminator: 0, file: !5, scope: !8)
diff --git a/llvm/test/Transforms/GCOVProfiling/linezero.ll b/llvm/test/Transforms/GCOVProfiling/linezero.ll
new file mode 100644
index 00000000000..7c084a3ec18
--- /dev/null
+++ b/llvm/test/Transforms/GCOVProfiling/linezero.ll
@@ -0,0 +1,145 @@
+; RUN: rm -rf %t && mkdir -p %t
+
+; RUN: sed -e 's|PATTERN|%/t|g' %s | opt -insert-gcov-profiling -disable-output
+; RUN: rm %t/linezero.gcno
+
+; RUN: sed -e 's|PATTERN|%/t|g' %s | opt -passes=insert-gcov-profiling -disable-output
+; RUN: rm %t/linezero.gcno
+
+; This is a crash test.
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+%struct.vector = type { i8 }
+
+; Function Attrs: nounwind
+define i32 @_Z4testv() #0 !dbg !15 {
+entry:
+  %retval = alloca i32, align 4
+  %__range = alloca %struct.vector*, align 8
+  %ref.tmp = alloca %struct.vector, align 1
+  %undef.agg.tmp = alloca %struct.vector, align 1
+  %__begin = alloca i8*, align 8
+  %__end = alloca i8*, align 8
+  %spec = alloca i8, align 1
+  call void @llvm.dbg.declare(metadata %struct.vector** %__range, metadata !27, metadata !DIExpression()), !dbg !30
+  br label %0
+
+; <label>:0                                       ; preds = %entry
+  call void @_Z13TagFieldSpecsv(), !dbg !31
+  store %struct.vector* %ref.tmp, %struct.vector** %__range, align 8, !dbg !31
+  call void @llvm.dbg.declare(metadata i8** %__begin, metadata !32, metadata !DIExpression()), !dbg !30
+  %1 = load %struct.vector*, %struct.vector** %__range, align 8, !dbg !31
+  %call = call i8* @_ZN6vector5beginEv(%struct.vector* %1), !dbg !31
+  store i8* %call, i8** %__begin, align 8, !dbg !31
+  call void @llvm.dbg.declare(metadata i8** %__end, metadata !33, metadata !DIExpression()), !dbg !30
+  %2 = load %struct.vector*, %struct.vector** %__range, align 8, !dbg !31
+  %call1 = call i8* @_ZN6vector3endEv(%struct.vector* %2), !dbg !31
+  store i8* %call1, i8** %__end, align 8, !dbg !31
+  br label %for.cond, !dbg !31
+
+for.cond:                                         ; preds = %for.inc, %0
+  %3 = load i8*, i8** %__begin, align 8, !dbg !34
+  %4 = load i8*, i8** %__end, align 8, !dbg !34
+  %cmp = icmp ne i8* %3, %4, !dbg !34
+  br i1 %cmp, label %for.body, label %for.end, !dbg !34
+
+for.body:                                         ; preds = %for.cond
+  call void @llvm.dbg.declare(metadata i8* %spec, metadata !37, metadata !DIExpression()), !dbg !31
+  %5 = load i8*, i8** %__begin, align 8, !dbg !38
+  %6 = load i8, i8* %5, align 1, !dbg !38
+  store i8 %6, i8* %spec, align 1, !dbg !38
+  br label %for.inc, !dbg !38
+
+for.inc:                                          ; preds = %for.body
+  %7 = load i8*, i8** %__begin, align 8, !dbg !40
+  %incdec.ptr = getelementptr inbounds i8, i8* %7, i32 1, !dbg !40
+  store i8* %incdec.ptr, i8** %__begin, align 8, !dbg !40
+  br label %for.cond, !dbg !40
+
+for.end:                                          ; preds = %for.cond
+  call void @llvm.trap(), !dbg !42
+  unreachable, !dbg !42
+
+return:                                           ; No predecessors!
+  %8 = load i32, i32* %retval, !dbg !44
+  ret i32 %8, !dbg !44
+}
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
+
+declare void @_Z13TagFieldSpecsv() #2
+
+declare i8* @_ZN6vector5beginEv(%struct.vector*) #2
+
+declare i8* @_ZN6vector3endEv(%struct.vector*) #2
+
+; Function Attrs: noreturn nounwind
+declare void @llvm.trap() #3
+
+; Function Attrs: nounwind
+define void @_Z2f1v() #0 !dbg !20 {
+entry:
+  br label %0
+
+; <label>:0                                       ; preds = %entry
+  ret void, !dbg !45
+}
+
+attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind readnone }
+attributes #2 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #3 = { noreturn nounwind }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!23, !24}
+!llvm.gcov = !{!25}
+!llvm.ident = !{!26}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.5.0 (trunk 209871)", isOptimized: false, emissionKind: FullDebug, file: !1, enums: !2, retainedTypes: !3, globals: !2, imports: !2)
+!1 = !DIFile(filename: "<stdin>", directory: "PATTERN")
+!2 = !{}
+!3 = !{!4}
+!4 = !DICompositeType(tag: DW_TAG_structure_type, name: "vector", line: 21, size: 8, align: 8, file: !5, elements: !6, identifier: "_ZTS6vector")
+!5 = !DIFile(filename: "linezero.cc", directory: "PATTERN")
+!6 = !{!7, !13}
+!7 = !DISubprogram(name: "begin", linkageName: "_ZN6vector5beginEv", line: 25, isLocal: false, isDefinition: false, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 25, file: !5, scope: !4, type: !8)
+!8 = !DISubroutineType(types: !9)
+!9 = !{!10, !12}
+!10 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, baseType: !11)
+!11 = !DIBasicType(tag: DW_TAG_base_type, name: "char", size: 8, align: 8, encoding: DW_ATE_signed_char)
+!12 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, flags: DIFlagArtificial | DIFlagObjectPointer, baseType: !4)
+!13 = !DISubprogram(name: "end", linkageName: "_ZN6vector3endEv", line: 26, isLocal: false, isDefinition: false, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 26, file: !5, scope: !4, type: !8)
+!15 = distinct !DISubprogram(name: "test", linkageName: "_Z4testv", line: 50, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 50, file: !5, scope: !16, type: !17, retainedNodes: !2)
+!16 = !DIFile(filename: "linezero.cc", directory: "PATTERN")
+!17 = !DISubroutineType(types: !18)
+!18 = !{!19}
+!19 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!20 = distinct !DISubprogram(name: "f1", linkageName: "_Z2f1v", line: 54, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 54, file: !5, scope: !16, type: !21, retainedNodes: !2)
+!21 = !DISubroutineType(types: !22)
+!22 = !{null}
+!23 = !{i32 2, !"Dwarf Version", i32 4}
+!24 = !{i32 2, !"Debug Info Version", i32 3}
+!25 = !{!"PATTERN/linezero.o", !0}
+!26 = !{!"clang version 3.5.0 (trunk 209871)"}
+!27 = !DILocalVariable(name: "__range", flags: DIFlagArtificial, scope: !28, type: !29)
+!28 = distinct !DILexicalBlock(line: 51, column: 0, file: !5, scope: !15)
+!29 = !DIDerivedType(tag: DW_TAG_rvalue_reference_type, baseType: !4)
+!30 = !DILocation(line: 0, scope: !28)
+!31 = !DILocation(line: 51, scope: !28)
+!32 = !DILocalVariable(name: "__begin", flags: DIFlagArtificial, scope: !28, type: !10)
+!33 = !DILocalVariable(name: "__end", flags: DIFlagArtificial, scope: !28, type: !10)
+!34 = !DILocation(line: 51, scope: !35)
+!35 = distinct !DILexicalBlock(line: 51, column: 0, file: !5, scope: !36)
+!36 = distinct !DILexicalBlock(line: 51, column: 0, file: !5, scope: !28)
+!37 = !DILocalVariable(name: "spec", line: 51, scope: !28, file: !16, type: !11)
+!38 = !DILocation(line: 51, scope: !39)
+!39 = distinct !DILexicalBlock(line: 51, column: 0, file: !5, scope: !28)
+!40 = !DILocation(line: 51, scope: !41)
+!41 = distinct !DILexicalBlock(line: 51, column: 0, file: !5, scope: !28)
+!42 = !DILocation(line: 51, scope: !43)
+!43 = distinct !DILexicalBlock(line: 51, column: 0, file: !5, scope: !28)
+!44 = !DILocation(line: 52, scope: !15)
+!45 = !DILocation(line: 54, scope: !20)
diff --git a/llvm/test/Transforms/GCOVProfiling/linkagename.ll b/llvm/test/Transforms/GCOVProfiling/linkagename.ll
new file mode 100644
index 00000000000..195d3a0f219
--- /dev/null
+++ b/llvm/test/Transforms/GCOVProfiling/linkagename.ll
@@ -0,0 +1,31 @@
+; RUN: rm -rf %t && mkdir -p %t
+; RUN: echo '!9 = !{!"%/t/linkagename.ll", !0}' > %t/1
+; RUN: cat %s %t/1 > %t/2
+; RUN: opt -insert-gcov-profiling -disable-output < %t/2
+; RUN: grep _Z3foov %t/linkagename.gcno
+; RUN: rm %t/linkagename.gcno
+
+; RUN: opt -passes=insert-gcov-profiling -disable-output < %t/2
+; RUN: grep _Z3foov %t/linkagename.gcno
+; RUN: rm %t/linkagename.gcno
+
+define void @_Z3foov() !dbg !5 {
+entry:
+  ret void, !dbg !8
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!10}
+!llvm.gcov = !{!9}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.3 (trunk 177323)", isOptimized: false, emissionKind: FullDebug, file: !2, enums: !3, retainedTypes: !3, globals: !3, imports:  !3)
+!1 = !DIFile(filename: "hello.cc", directory: "/home/nlewycky")
+!2 = !DIFile(filename: "hello.cc", directory: "/home/nlewycky")
+!3 = !{}
+!5 = distinct !DISubprogram(name: "foo", linkageName: "_Z3foov", line: 1, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 1, file: !1, scope: !1, type: !6, retainedNodes: !3)
+!6 = !DISubroutineType(types: !7)
+!7 = !{null}
+!8 = !DILocation(line: 1, scope: !5)
+
+
+!10 = !{i32 1, !"Debug Info Version", i32 3}
diff --git a/llvm/test/Transforms/GCOVProfiling/modules.ll b/llvm/test/Transforms/GCOVProfiling/modules.ll
new file mode 100644
index 00000000000..460d4dfdfa1
--- /dev/null
+++ b/llvm/test/Transforms/GCOVProfiling/modules.ll
@@ -0,0 +1,13 @@
+; RUN: opt -insert-gcov-profiling -o - < %s | llvm-dis | FileCheck -check-prefix=EMIT-ARCS %s
+; RUN: opt -passes=insert-gcov-profiling -o - < %s | llvm-dis | FileCheck -check-prefix=EMIT-ARCS %s
+
+; EMIT-ARCS-NOT: call void @llvm_gcda_start_file
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "LLVM", isOptimized: false, runtimeVersion: 2, splitDebugFilename: "my.dwo", emissionKind: FullDebug, enums: !2, retainedTypes: !2, globals: !2, imports: !2, dwoId: 43981)
+!1 = !DIFile(filename: "<stdin>", directory: "/")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
diff --git a/llvm/test/Transforms/GCOVProfiling/return-block.ll b/llvm/test/Transforms/GCOVProfiling/return-block.ll
new file mode 100644
index 00000000000..74812d14c64
--- /dev/null
+++ b/llvm/test/Transforms/GCOVProfiling/return-block.ll
@@ -0,0 +1,84 @@
+; Inject metadata to set the .gcno file location
+; RUN: rm -rf %t && mkdir -p %t
+; RUN: echo '!19 = !{!"%/t/return-block.ll", !0}' > %t/1
+; RUN: cat %s %t/1 > %t/2
+
+; By default, the return block is last.
+; RUN: opt -insert-gcov-profiling -disable-output %t/2
+; RUN: llvm-cov gcov -n -dump %t/return-block.gcno 2>&1 | FileCheck -check-prefix=CHECK -check-prefix=RETURN-LAST %s
+
+; But we can optionally emit it second, to match newer gcc versions.
+; RUN: opt -insert-gcov-profiling -gcov-exit-block-before-body -disable-output %t/2
+; RUN: llvm-cov gcov -n -dump %t/return-block.gcno 2>&1 | FileCheck -check-prefix=CHECK -check-prefix=RETURN-SECOND %s
+; RUN: rm  %t/return-block.gcno
+
+; By default, the return block is last.
+; RUN: opt -passes=insert-gcov-profiling -disable-output %t/2
+; RUN: llvm-cov gcov -n -dump %t/return-block.gcno 2>&1 | FileCheck -check-prefix=CHECK -check-prefix=RETURN-LAST %s
+
+; But we can optionally emit it second, to match newer gcc versions.
+; RUN: opt -passes=insert-gcov-profiling -gcov-exit-block-before-body -disable-output %t/2
+; RUN: llvm-cov gcov -n -dump %t/return-block.gcno 2>&1 | FileCheck -check-prefix=CHECK -check-prefix=RETURN-SECOND %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@A = common global i32 0, align 4, !dbg !9
+
+; Function Attrs: nounwind uwtable
+define void @test() #0 !dbg !4 {
+entry:
+  tail call void (...) @f() #2, !dbg !14
+  %0 = load i32, i32* @A, align 4, !dbg !15
+  %tobool = icmp eq i32 %0, 0, !dbg !15
+  br i1 %tobool, label %if.end, label %if.then, !dbg !15
+
+if.then:                                          ; preds = %entry
+  tail call void (...) @g() #2, !dbg !16
+  br label %if.end, !dbg !16
+
+if.end:                                           ; preds = %entry, %if.then
+  ret void, !dbg !18
+}
+
+declare void @f(...) #1
+
+declare void @g(...) #1
+
+attributes #0 = { nounwind uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #2 = { nounwind }
+
+!llvm.gcov = !{!19}
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!11, !12}
+!llvm.ident = !{!13}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "clang version 3.6.0 (trunk 223182)", isOptimized: true, emissionKind: FullDebug, file: !1, enums: !2, retainedTypes: !2, globals: !8, imports: !2)
+!1 = !DIFile(filename: ".../llvm/test/Transforms/GCOVProfiling/return-block.ll", directory: "")
+!2 = !{}
+!4 = distinct !DISubprogram(name: "test", line: 5, isLocal: false, isDefinition: true, isOptimized: true, unit: !0, scopeLine: 5, file: !1, scope: !5, type: !6, retainedNodes: !2)
+!5 = !DIFile(filename: ".../llvm/test/Transforms/GCOVProfiling/return-block.ll", directory: "")
+!6 = !DISubroutineType(types: !7)
+!7 = !{null}
+!8 = !{!9}
+!9 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "A", line: 3, isLocal: false, isDefinition: true, scope: null, file: !5, type: !10), expr: !DIExpression())
+!10 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
+!11 = !{i32 2, !"Dwarf Version", i32 4}
+!12 = !{i32 2, !"Debug Info Version", i32 3}
+!13 = !{!"clang version 3.6.0 (trunk 223182)"}
+!14 = !DILocation(line: 6, column: 3, scope: !4)
+!15 = !DILocation(line: 7, column: 7, scope: !4)
+!16 = !DILocation(line: 8, column: 5, scope: !17)
+!17 = distinct !DILexicalBlock(line: 7, column: 7, file: !1, scope: !4)
+!18 = !DILocation(line: 9, column: 1, scope: !4)
+
+; There should be no destination edges for the exit block.
+; CHECK: Block : 1 Counter : 0
+; RETURN-LAST:       Destination Edges
+; RETURN-SECOND-NOT: Destination Edges
+; CHECK: Block : 2 Counter : 0
+; CHECK: Block : 4 Counter : 0
+; RETURN-LAST-NOT: Destination Edges
+; RETURN-SECOND:   Destination Edges
+; CHECK-NOT: Block :
diff --git a/llvm/test/Transforms/GCOVProfiling/three-element-mdnode.ll b/llvm/test/Transforms/GCOVProfiling/three-element-mdnode.ll
new file mode 100644
index 00000000000..0af01188986
--- /dev/null
+++ b/llvm/test/Transforms/GCOVProfiling/three-element-mdnode.ll
@@ -0,0 +1,28 @@
+; RUN: rm -rf %t && mkdir -p %t
+; RUN: echo '!10 = !{!"%/t/aaa.gcno", !"%/t/bbb.gcda", !0}' > %t/1
+; RUN: cat %s %t/1 > %t/2
+; RUN: opt -insert-gcov-profiling -S -o %t/3 < %t/2
+; RUN: grep _Z3foov %t/aaa.gcno
+; RUN: grep bbb.gcda %t/3
+; RUN: rm %t/aaa.gcno
+
+define void @_Z3foov() !dbg !5 {
+entry:
+  ret void, !dbg !8
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!9}
+!llvm.gcov = !{!10}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.3 (trunk 177323)", isOptimized: false, emissionKind: FullDebug, file: !2, enums: !3, retainedTypes: !3, globals: !3, imports:  !3)
+!1 = !DIFile(filename: "hello.cc", directory: "/home/nlewycky")
+!2 = !DIFile(filename: "hello.cc", directory: "/home/nlewycky")
+!3 = !{}
+!5 = distinct !DISubprogram(name: "foo", linkageName: "_Z3foov", line: 1, virtualIndex: 6, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, scopeLine: 1, file: !1, scope: !1, type: !6, retainedNodes: !3)
+!6 = !DISubroutineType(types: !7)
+!7 = !{null}
+!8 = !DILocation(line: 1, scope: !5)
+
+
+!9 = !{i32 1, !"Debug Info Version", i32 3}
diff --git a/llvm/test/Transforms/GCOVProfiling/version.ll b/llvm/test/Transforms/GCOVProfiling/version.ll
new file mode 100644
index 00000000000..239c62f4a6b
--- /dev/null
+++ b/llvm/test/Transforms/GCOVProfiling/version.ll
@@ -0,0 +1,38 @@
+; RUN: rm -rf %t && mkdir -p %t
+; RUN: echo '!9 = !{!"%/t/version.ll", !0}' > %t/1
+; RUN: cat %s %t/1 > %t/2
+; RUN: opt -insert-gcov-profiling -disable-output < %t/2
+; RUN: head -c8 %t/version.gcno | grep '^oncg.204'
+; RUN: rm %t/version.gcno
+; RUN: not opt -insert-gcov-profiling -default-gcov-version=asdfasdf -disable-output < %t/2
+; RUN: opt -insert-gcov-profiling -default-gcov-version=407* -disable-output < %t/2
+; RUN: head -c8 %t/version.gcno | grep '^oncg.704'
+; RUN: rm %t/version.gcno
+
+; RUN: opt -passes=insert-gcov-profiling -disable-output < %t/2
+; RUN: head -c8 %t/version.gcno | grep '^oncg.204'
+; RUN: rm %t/version.gcno
+; RUN: not opt -passes=insert-gcov-profiling -default-gcov-version=asdfasdf -disable-output < %t/2
+; RUN: opt -passes=insert-gcov-profiling -default-gcov-version=407* -disable-output < %t/2
+; RUN: head -c8 %t/version.gcno | grep '^oncg.704'
+; RUN: rm %t/version.gcno
+
+define void @test() !dbg !5 {
+  ret void, !dbg !8
+}
+
+!llvm.gcov = !{!9}
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!12}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.3 (trunk 176994)", isOptimized: false, emissionKind: FullDebug, file: !11, enums: !3, retainedTypes: !3, globals: !3)
+!2 = !DIFile(filename: "version", directory: "/usr/local/google/home/nlewycky")
+!3 = !{}
+!5 = distinct !DISubprogram(name: "test", line: 1, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 1, file: !10, scope: !6, type: !7, retainedNodes: !3)
+!6 = !DIFile(filename: "<stdin>", directory: ".")
+!7 = !DISubroutineType(types: !{null})
+!8 = !DILocation(line: 1, scope: !5)
+;; !9 is added through the echo line at the top.
+!10 = !DIFile(filename: "<stdin>", directory: ".")
+!11 = !DIFile(filename: "version", directory: "/usr/local/google/home/nlewycky")
+!12 = !{i32 1, !"Debug Info Version", i32 3}