Update entry count for cold calls

Summary:
Profile sample files include the number of times each entry or inlined
call site is sampled. This is translated into the entry count metadta
on functions.

When sample data is being read, if a call site that was inlined
in the sample program is considered cold and not inlined, then
the entry count of the out-of-line functions does not reflect
the current compilation.

In this patch, we note call sites where the function was not inlined
and as a last action of the sample profile loading, we update the
called function's entry count to reflect the calls from these
call sites which are not included in the profile file.

Reviewers: danielcdh, wmi, Kader, modocache

Reviewed By: wmi

Subscribers: davidxl, eraman, llvm-commits

Differential Revision: https://reviews.llvm.org/D52845

llvm-svn: 352001

2 files changed, 190 insertions, 0 deletions

diff --git a/llvm/test/Transforms/SampleProfile/Inputs/entry_counts_cold.prof b/llvm/test/Transforms/SampleProfile/Inputs/entry_counts_cold.prof
new file mode 100644
index 00000000000..cd7e871d6c2
--- /dev/null
+++ b/llvm/test/Transforms/SampleProfile/Inputs/entry_counts_cold.prof
@@ -0,0 +1,20 @@
+top:200:100
+ 1: 100 foo:100
+ 2: 100
+ 3: 2
+ 4: 100
+ 1: foo:100
+    2: 100
+    3: 100 bar:100
+    4: 100
+ 3: bar:2
+    1: 2
+    2: 2
+foo:200:150
+ 2: 150
+ 3: 150  bar:150
+ 4: 150
+bar:450:300
+ 1: 300 baz:300
+ 2: 300
+ 3: 300
diff --git a/llvm/test/Transforms/SampleProfile/entry_counts_cold.ll b/llvm/test/Transforms/SampleProfile/entry_counts_cold.ll
new file mode 100644
index 00000000000..da60ebec6d5
--- /dev/null
+++ b/llvm/test/Transforms/SampleProfile/entry_counts_cold.ll
@@ -0,0 +1,170 @@
+; RUN: opt < %s -sample-profile -sample-profile-file=%S/Inputs/entry_counts_cold.prof -S | FileCheck %s
+; ModuleID = 'temp.bc'
+source_filename = "temp.c"
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.14.0"
+
+; Function Attrs: nounwind ssp uwtable
+; CHECK: define i32 @top({{.*}} !prof [[TOP:![0-9]+]] 
+define i32 @top(i32* %p) #0 !dbg !8 {
+entry:
+  %p.addr = alloca i32*, align 8
+  store i32* %p, i32** %p.addr, align 8, !tbaa !15
+  call void @llvm.dbg.declare(metadata i32** %p.addr, metadata !14, metadata !DIExpression()), !dbg !19
+  %0 = load i32*, i32** %p.addr, align 8, !dbg !20, !tbaa !15
+  %call = call i32 @foo(i32* %0), !dbg !21
+; foo is inlined
+; CHECK-NOT: call i32 @foo
+; CHECK: call i32 @bar
+  %1 = load i32*, i32** %p.addr, align 8, !dbg !22, !tbaa !15
+  %2 = load i32, i32* %1, align 4, !dbg !24, !tbaa !25
+  %tobool = icmp ne i32 %2, 0, !dbg !24
+  br i1 %tobool, label %if.then, label %if.end, !dbg !27
+
+if.then:                                          ; preds = %entry
+  %3 = load i32*, i32** %p.addr, align 8, !dbg !28, !tbaa !15
+; bar is not inlined
+; CHECK: call i32 @bar
+  %call1 = call i32 @bar(i32* %3), !dbg !29
+  br label %if.end, !dbg !29
+
+if.end:                                           ; preds = %if.then, %entry
+  ret i32 0, !dbg !30
+}
+
+; Function Attrs: nounwind readnone speculatable
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
+
+; Function Attrs: nounwind ssp uwtable
+; CHECK: define i32 @foo({{.*}} !prof [[FOO:![0-9]+]] 
+define i32 @foo(i32* %p) #0 !dbg !31 {
+entry:
+  %p.addr = alloca i32*, align 8
+  %a = alloca i32, align 4
+  store i32* %p, i32** %p.addr, align 8, !tbaa !15
+  call void @llvm.dbg.declare(metadata i32** %p.addr, metadata !33, metadata !DIExpression()), !dbg !35
+  %0 = bitcast i32* %a to i8*, !dbg !36
+  call void @llvm.lifetime.start.p0i8(i64 4, i8* %0) #4, !dbg !36
+  call void @llvm.dbg.declare(metadata i32* %a, metadata !34, metadata !DIExpression()), !dbg !37
+  %1 = load i32*, i32** %p.addr, align 8, !dbg !38, !tbaa !15
+  %arrayidx = getelementptr inbounds i32, i32* %1, i64 3, !dbg !38
+  %2 = load i32, i32* %arrayidx, align 4, !dbg !38, !tbaa !25
+  %3 = load i32*, i32** %p.addr, align 8, !dbg !39, !tbaa !15
+  %arrayidx1 = getelementptr inbounds i32, i32* %3, i64 2, !dbg !39
+  %4 = load i32, i32* %arrayidx1, align 4, !dbg !40, !tbaa !25
+  %add = add nsw i32 %4, %2, !dbg !40
+  store i32 %add, i32* %arrayidx1, align 4, !dbg !40, !tbaa !25
+  %5 = load i32*, i32** %p.addr, align 8, !dbg !41, !tbaa !15
+  %call = call i32 @bar(i32* %5), !dbg !42
+  store i32 %call, i32* %a, align 4, !dbg !43, !tbaa !25
+  %6 = load i32, i32* %a, align 4, !dbg !44, !tbaa !25
+  %add2 = add nsw i32 %6, 1, !dbg !45
+  %7 = bitcast i32* %a to i8*, !dbg !46
+  call void @llvm.lifetime.end.p0i8(i64 4, i8* %7) #4, !dbg !46
+  ret i32 %add2, !dbg !47
+}
+
+; Function Attrs: nounwind ssp uwtable
+; CHECK: define i32 @bar({{.*}} !prof [[BAR:![0-9]+]] 
+define i32 @bar(i32* %p) #0 !dbg !48 {
+entry:
+  %p.addr = alloca i32*, align 8
+  store i32* %p, i32** %p.addr, align 8, !tbaa !15
+  call void @llvm.dbg.declare(metadata i32** %p.addr, metadata !50, metadata !DIExpression()), !dbg !51
+  ; CHECK: call void (...) @baz{{.*}} !prof [[BAZ:![0-9]+]]
+  call void (...) @baz(), !dbg !52
+  %0 = load i32*, i32** %p.addr, align 8, !dbg !53, !tbaa !15
+  %arrayidx = getelementptr inbounds i32, i32* %0, i64 2, !dbg !53
+  %1 = load i32, i32* %arrayidx, align 4, !dbg !53, !tbaa !25
+  %2 = load i32*, i32** %p.addr, align 8, !dbg !54, !tbaa !15
+  %arrayidx1 = getelementptr inbounds i32, i32* %2, i64 1, !dbg !54
+  %3 = load i32, i32* %arrayidx1, align 4, !dbg !55, !tbaa !25
+  %add = add nsw i32 %3, %1, !dbg !55
+  store i32 %add, i32* %arrayidx1, align 4, !dbg !55, !tbaa !25
+  %4 = load i32*, i32** %p.addr, align 8, !dbg !56, !tbaa !15
+  %arrayidx2 = getelementptr inbounds i32, i32* %4, i64 3, !dbg !56
+  %5 = load i32, i32* %arrayidx2, align 4, !dbg !56, !tbaa !25
+  ret i32 %5, !dbg !57
+}
+
+; Function Attrs: argmemonly nounwind
+declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) #2
+
+; Function Attrs: argmemonly nounwind
+declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) #2
+
+declare void @baz(...) #3
+
+attributes #0 = { nounwind ssp uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="penryn" "target-features"="+cx16,+fxsr,+mmx,+sahf,+sse,+sse2,+sse3,+sse4.1,+ssse3,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind readnone speculatable }
+attributes #2 = { argmemonly nounwind }
+attributes #3 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="penryn" "target-features"="+cx16,+fxsr,+mmx,+sahf,+sse,+sse2,+sse3,+sse4.1,+ssse3,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #4 = { nounwind }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4, !5, !6}
+!llvm.ident = !{!7}
+
+; CHECK: [[TOP]] = !{!"function_entry_count", i64 101}
+; CHECK: [[FOO]] = !{!"function_entry_count", i64 151}
+; CHECK: [[BAR]] = !{!"function_entry_count", i64 303}
+; CHECK: [[BAZ]] = !{!"branch_weights", i64 303}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 8.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: GNU)
+!1 = !DIFile(filename: "temp.c", directory: "llvm/test/Transforms/SampleProfile")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = !{i32 1, !"wchar_size", i32 4}
+!6 = !{i32 7, !"PIC Level", i32 2}
+!7 = !{!"clang version 8.0.0"}
+!8 = distinct !DISubprogram(name: "top", scope: !1, file: !1, line: 5, type: !9, scopeLine: 5, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !13)
+!9 = !DISubroutineType(types: !10)
+!10 = !{!11, !12}
+!11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!12 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !11, size: 64)
+!13 = !{!14}
+!14 = !DILocalVariable(name: "p", arg: 1, scope: !8, file: !1, line: 5, type: !12)
+!15 = !{!16, !16, i64 0}
+!16 = !{!"any pointer", !17, i64 0}
+!17 = !{!"omnipotent char", !18, i64 0}
+!18 = !{!"Simple C/C++ TBAA"}
+!19 = !DILocation(line: 5, column: 14, scope: !8)
+!20 = !DILocation(line: 6, column: 7, scope: !8)
+!21 = !DILocation(line: 6, column: 3, scope: !8)
+!22 = !DILocation(line: 7, column: 8, scope: !23)
+!23 = distinct !DILexicalBlock(scope: !8, file: !1, line: 7, column: 7)
+!24 = !DILocation(line: 7, column: 7, scope: !23)
+!25 = !{!26, !26, i64 0}
+!26 = !{!"int", !17, i64 0}
+!27 = !DILocation(line: 7, column: 7, scope: !8)
+!28 = !DILocation(line: 8, column: 9, scope: !23)
+!29 = !DILocation(line: 8, column: 5, scope: !23)
+!30 = !DILocation(line: 9, column: 3, scope: !8)
+!31 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 12, type: !9, scopeLine: 12, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !32)
+!32 = !{!33, !34}
+!33 = !DILocalVariable(name: "p", arg: 1, scope: !31, file: !1, line: 12, type: !12)
+!34 = !DILocalVariable(name: "a", scope: !31, file: !1, line: 13, type: !11)
+!35 = !DILocation(line: 12, column: 14, scope: !31)
+!36 = !DILocation(line: 13, column: 3, scope: !31)
+!37 = !DILocation(line: 13, column: 7, scope: !31)
+!38 = !DILocation(line: 14, column: 11, scope: !31)
+!39 = !DILocation(line: 14, column: 3, scope: !31)
+!40 = !DILocation(line: 14, column: 8, scope: !31)
+!41 = !DILocation(line: 15, column: 11, scope: !31)
+!42 = !DILocation(line: 15, column: 7, scope: !31)
+!43 = !DILocation(line: 15, column: 5, scope: !31)
+!44 = !DILocation(line: 16, column: 10, scope: !31)
+!45 = !DILocation(line: 16, column: 11, scope: !31)
+!46 = !DILocation(line: 17, column: 1, scope: !31)
+!47 = !DILocation(line: 16, column: 3, scope: !31)
+!48 = distinct !DISubprogram(name: "bar", scope: !1, file: !1, line: 19, type: !9, scopeLine: 19, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !49)
+!49 = !{!50}
+!50 = !DILocalVariable(name: "p", arg: 1, scope: !48, file: !1, line: 19, type: !12)
+!51 = !DILocation(line: 19, column: 15, scope: !48)
+!52 = !DILocation(line: 20, column: 3, scope: !48)
+!53 = !DILocation(line: 21, column: 11, scope: !48)
+!54 = !DILocation(line: 21, column: 3, scope: !48)
+!55 = !DILocation(line: 21, column: 8, scope: !48)
+!56 = !DILocation(line: 22, column: 10, scope: !48)
+!57 = !DILocation(line: 22, column: 3, scope: !48)