[llvm] [SampleFDO] Read call-graph matching recovered top-level function profile (PR #101053)

[Lei Wang via llvm-commits]

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@@ -0,0 +1,258 @@
+; REQUIRES: x86_64-linux
+; REQUIRES: asserts
+; RUN: opt < %s -passes=sample-profile -sample-profile-file=%S/Inputs/pseudo-probe-stale-profile-toplev-func.prof --salvage-stale-profile --salvage-unused-profile -report-profile-staleness -S --debug-only=sample-profile,sample-profile-matcher,sample-profile-impl -pass-remarks=inline --min-call-count-for-cg-matching=0 --min-func-count-for-cg-matching=0 2>&1 | FileCheck %s -check-prefix=CHECK-TEXT
+; RUN: llvm-profdata merge --sample %S/Inputs/pseudo-probe-stale-profile-toplev-func.prof -extbinary -o %t.extbinary
+; RUN: opt < %s -passes=sample-profile -sample-profile-file=%t.extbinary --salvage-stale-profile --salvage-unused-profile -report-profile-staleness -S --debug-only=sample-profile,sample-profile-matcher,sample-profile-impl -pass-remarks=inline --min-call-count-for-cg-matching=0 --min-func-count-for-cg-matching=0 2>&1 | FileCheck %s -check-prefix=CHECK-EXTBIN
+
+; CHECK-TEXT: Run stale profile matching for main
+; CHECK-TEXT-NOT: Read top-level function foo for call-graph matching
+; CHECK-TEXT: The checksums for foo_rename(IR) and foo(Profile) match.
+; CHECK-TEXT: Function:foo_rename matches profile:foo
+; CHECK-TEXT: Run stale profile matching for foo_rename
+; CHECK-TEXT-NOT: Top-level function foo is recovered and re-read by the sample reader.
+; CHECK-TEXT: (1/3) of functions' profile are matched and (2724522/3177413) of samples are reused by call graph matching.
+
+; CHECK-TEXT: Processing Function main
+; CHECK-TEXT:     5:  call void @foo_rename(), !dbg ![[#]] - weight: 51
+; CHECK-TEXT: Processing Function foo_rename
+; CHECK-TEXT:     11:  %call = call i32 @bar(i32 noundef %5), !dbg ![[#]] - weight: 452687
+
+
+; CHECK-EXTBIN: Run stale profile matching for main
+; CHECK-EXTBIN: Read top-level function foo for call-graph matching
+; CHECK-EXTBIN: The checksums for foo_rename(IR) and foo(Profile) match.
+; CHECK-EXTBIN: Function:foo_rename matches profile:foo
+; CHECK-EXTBIN: Run stale profile matching for foo_rename
+; CHECK-EXTBIN: Top-level function foo is recovered and re-read by the sample reader.
+; CHECK-EXTBIN: (1/3) of functions' profile are matched and (2724522/3177413) of samples are reused by call graph matching.
+
+; CHECK-EXTBIN: Processing Function main
+; CHECK-EXTBIN:     5:  call void @foo_rename(), !dbg ![[#]] - weight: 51
+; CHECK-EXTBIN: Processing Function foo_rename
+; CHECK-EXTBIN:     11:  %call = call i32 @bar(i32 noundef %5), !dbg ![[#]] - weight: 452687
+
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+ at x = dso_local global i32 0, align 4, !dbg !0
+
+; Function Attrs: noinline nounwind uwtable
+define dso_local i32 @bar(i32 noundef %x) #0 !dbg !18 {
+entry:
+    #dbg_value(i32 %x, !22, !DIExpression(), !23)
+  call void @llvm.pseudoprobe(i64 -2012135647395072713, i64 1, i32 0, i64 -1), !dbg !24
+  %add = add nsw i32 %x, 1, !dbg !25
+  ret i32 %add, !dbg !26
+}
+
+; Function Attrs: noinline nounwind uwtable
+define dso_local void @foo_rename() #0 !dbg !27 {
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wlei-llvm wrote:

Removed the control flow for this function.

https://github.com/llvm/llvm-project/pull/101053