[compiler-rt] [llvm] [ThinLTO][TypeProf] Allow importing of local-linkage global variables in mod1:func_foo->mod2:func_bar -> mod2:local-var chain (PR #100448)

Mingming Liu via llvm-commits llvm-commits at lists.llvm.org
Wed Jul 24 12:34:53 PDT 2024


https://github.com/minglotus-6 updated https://github.com/llvm/llvm-project/pull/100448

>From 1be94de97494770f898cb8febfd3e9698a97aa6a Mon Sep 17 00:00:00 2001
From: mingmingl <mingmingl at google.com>
Date: Tue, 23 Jul 2024 10:13:02 -0700
Subject: [PATCH 1/3] [InstrFDO]Import assume unique local

---
 llvm/lib/Transforms/IPO/FunctionImport.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp
index 038785114a0cf..2e20f87400e1d 100644
--- a/llvm/lib/Transforms/IPO/FunctionImport.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp
@@ -174,6 +174,11 @@ static cl::opt<std::string> WorkloadDefinitions(
              "}"),
     cl::Hidden);
 
+static cl::opt<bool> ImportAssumeUniqueLocal(
+    "import-assume-unique-local", cl::init(false),
+    cl::description("assume local-linkage global variables have unique names"),
+    cl::Hidden);
+
 namespace llvm {
 extern cl::opt<bool> EnableMemProfContextDisambiguation;
 }
@@ -367,6 +372,8 @@ class GlobalsImporter final {
       // was not distinguishing path.
       auto LocalNotInModule =
           [&](const GlobalValueSummary *RefSummary) -> bool {
+        if (ImportAssumeUniqueLocal)
+          return false;
         return GlobalValue::isLocalLinkage(RefSummary->linkage()) &&
                RefSummary->modulePath() != Summary.modulePath();
       };

>From 78fe701864317f6e46d673beb46af5acf69147a3 Mon Sep 17 00:00:00 2001
From: mingmingl <mingmingl at google.com>
Date: Wed, 24 Jul 2024 11:38:10 -0700
Subject: [PATCH 2/3] update test case

---
 .../Linux/instrprof-vtable-value-prof.cpp     | 30 ++++++++++++++-----
 llvm/lib/Transforms/IPO/FunctionImport.cpp    |  9 +++++-
 2 files changed, 30 insertions(+), 9 deletions(-)

diff --git a/compiler-rt/test/profile/Linux/instrprof-vtable-value-prof.cpp b/compiler-rt/test/profile/Linux/instrprof-vtable-value-prof.cpp
index 411640fc5176d..4ef7b2da2f572 100644
--- a/compiler-rt/test/profile/Linux/instrprof-vtable-value-prof.cpp
+++ b/compiler-rt/test/profile/Linux/instrprof-vtable-value-prof.cpp
@@ -1,3 +1,4 @@
+
 // REQUIRES: lld, lld-available
 
 // Building the instrumented binary will fail because lld doesn't support
@@ -5,7 +6,7 @@
 // ld.lld: error: /lib/../lib64/Scrt1.o: ABI version 1 is not supported
 // UNSUPPORTED: ppc && host-byteorder-big-endian
 
-// RUN: rm -rf %t && mkdir %t && cd %t
+// RUN: rm -rf %t && split-file %s %t && cd %t
 
 // RUN: %clangxx_pgogen -fuse-ld=lld -O2 -fprofile-generate=. -mllvm -enable-vtable-value-profiling %s -o test
 // RUN: env LLVM_PROFILE_FILE=test.profraw ./test
@@ -141,18 +142,19 @@
 // RUN:    -g -flto=thin -fwhole-program-vtables -fno-split-lto-unit -O2 \
 // RUN:    -mllvm -enable-vtable-value-profiling -Wl,-mllvm,-enable-vtable-value-profiling \
 // RUN:    -mllvm -enable-vtable-profile-use \
+// RUN:    -Wl,-plugin-opt,-import-assume-unique-local \
 // RUN:    -Wl,-mllvm,-enable-vtable-profile-use -Rpass=pgo-icall-prom \
 // RUN:    -Wl,-mllvm,-print-after=pgo-icall-prom \
 // RUN:    -Wl,-mllvm,-filter-print-funcs=main %s 2>&1 \
 // RUN:    | FileCheck %s --check-prefixes=REMARK,IR --implicit-check-not="!VP"
 
 // For the indirect call site `ptr->func`
-// REMARK: instrprof-vtable-value-prof.cpp:226:19: Promote indirect call to _ZN12_GLOBAL__N_18Derived24funcEii with count 150 out of 200, sink 1 instruction(s) and compare 1 vtable(s): {_ZTVN12_GLOBAL__N_18Derived2E}
-// REMARK: instrprof-vtable-value-prof.cpp:226:19: Promote indirect call to _ZN8Derived14funcEii with count 50 out of 50, sink 1 instruction(s) and compare 1 vtable(s): {_ZTV8Derived1}
+// REMARK: instrprof-vtable-value-prof.cpp:240:19: Promote indirect call to _ZN12_GLOBAL__N_18Derived24funcEii with count 150 out of 200, sink 1 instruction(s) and compare 1 vtable(s): {_ZTVN12_GLOBAL__N_18Derived2E}
+// REMARK: instrprof-vtable-value-prof.cpp:240:19: Promote indirect call to _ZN8Derived14funcEii with count 50 out of 50, sink 1 instruction(s) and compare 1 vtable(s): {_ZTV8Derived1}
 //
 // For the indirect call site `delete ptr`
-// REMARK: instrprof-vtable-value-prof.cpp:228:5: Promote indirect call to _ZN12_GLOBAL__N_18Derived2D0Ev with count 750 out of 1000, sink 2 instruction(s) and compare 1 vtable(s): {_ZTVN12_GLOBAL__N_18Derived2E}
-// REMARK: instrprof-vtable-value-prof.cpp:228:5: Promote indirect call to _ZN8Derived1D0Ev with count 250 out of 250, sink 2 instruction(s) and compare 1 vtable(s): {_ZTV8Derived1}
+// REMARK: instrprof-vtable-value-prof.cpp:242:5: Promote indirect call to _ZN12_GLOBAL__N_18Derived2D0Ev with count 750 out of 1000, sink 2 instruction(s) and compare 1 vtable(s): {_ZTVN12_GLOBAL__N_18Derived2E}
+// REMARK: instrprof-vtable-value-prof.cpp:242:5: Promote indirect call to _ZN8Derived1D0Ev with count 250 out of 250, sink 2 instruction(s) and compare 1 vtable(s): {_ZTV8Derived1}
 
 // The IR matchers for indirect callsite `ptr->func`.
 // IR-LABEL: @main
@@ -185,6 +187,7 @@
 // IR: [[MERGE0]]:
 // IR:    [[RES2:%.*]] = phi i32 [ [[RES1]], %[[MERGE1]] ], [ [[RESBB1]], %[[BB1]] ]
 
+//--- lib.h
 #include <stdio.h>
 #include <stdlib.h>
 class Base {
@@ -193,21 +196,31 @@ class Base {
 
   virtual ~Base() {};
 };
+
 class Derived1 : public Base {
 public:
-  int func(int a, int b) override { return a * b; }
+  int func(int a, int b) override;
 
   ~Derived1() {}
 };
 namespace {
 class Derived2 : public Base {
 public:
-  int func(int a, int b) override { return a * (a - b); }
+  int func(int a, int b) override;
 
   ~Derived2() {}
 };
 } // namespace
-__attribute__((noinline)) Base *createType(int a) {
+
+__attribute__((noinline)) Base *createType(int a);
+
+//-- lib.cpp
+
+int Derived1::func(int a, int b) { return a * b; }
+
+int Derived2::func(int a, int b) { return a * (a - b); }
+
+Base *createType(int a) {
   Base *base = nullptr;
   if (a % 4 == 0)
     base = new Derived1();
@@ -216,6 +229,7 @@ __attribute__((noinline)) Base *createType(int a) {
   return base;
 }
 
+//--- main.cpp
 int main(int argc, char **argv) {
   int sum = 0;
   for (int i = 0; i < 1000; i++) {
diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp
index 2e20f87400e1d..839c09fa9d586 100644
--- a/llvm/lib/Transforms/IPO/FunctionImport.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp
@@ -176,7 +176,14 @@ static cl::opt<std::string> WorkloadDefinitions(
 
 static cl::opt<bool> ImportAssumeUniqueLocal(
     "import-assume-unique-local", cl::init(false),
-    cl::description("assume local-linkage global variables have unique names"),
+    cl::desc(
+        "By default, a local-linkage global variable won't be imported in the "
+        "edge mod1:func -> mod2:func_bar -> mod2:local-var since compiler "
+        "cannot assume mod2 is compiled with full path or local-var has a "
+        "unique GUID. "
+        "Set this option to true will help cross-module import of such "
+        "variables. But it is only safe if the compiler user specify the full "
+        "module path."),
     cl::Hidden);
 
 namespace llvm {

>From d47ce4e4d56756f54ff0ed18b7f3269ff9d278ae Mon Sep 17 00:00:00 2001
From: mingmingl <mingmingl at google.com>
Date: Wed, 24 Jul 2024 12:34:31 -0700
Subject: [PATCH 3/3] fix test to make it pass at HEAD

---
 .../Linux/instrprof-vtable-value-prof.cpp     | 62 ++++++++++---------
 llvm/lib/Transforms/IPO/FunctionImport.cpp    |  4 ++
 2 files changed, 36 insertions(+), 30 deletions(-)

diff --git a/compiler-rt/test/profile/Linux/instrprof-vtable-value-prof.cpp b/compiler-rt/test/profile/Linux/instrprof-vtable-value-prof.cpp
index 4ef7b2da2f572..1d8a0f470310c 100644
--- a/compiler-rt/test/profile/Linux/instrprof-vtable-value-prof.cpp
+++ b/compiler-rt/test/profile/Linux/instrprof-vtable-value-prof.cpp
@@ -6,9 +6,9 @@
 // ld.lld: error: /lib/../lib64/Scrt1.o: ABI version 1 is not supported
 // UNSUPPORTED: ppc && host-byteorder-big-endian
 
-// RUN: rm -rf %t && split-file %s %t && cd %t
+// RUN: rm -rf %t && mkdir %t && split-file %s %t && cd %t
 
-// RUN: %clangxx_pgogen -fuse-ld=lld -O2 -fprofile-generate=. -mllvm -enable-vtable-value-profiling %s -o test
+// RUN: %clangxx_pgogen -fuse-ld=lld -O2 -fprofile-generate=. -mllvm -enable-vtable-value-profiling lib.cpp main.cpp -o test
 // RUN: env LLVM_PROFILE_FILE=test.profraw ./test
 
 // Show vtable profiles from raw profile.
@@ -38,23 +38,23 @@
 // COMMON-NEXT:  Number of instrumented vtables: 2
 // RAW:  Indirect Target Results:
 // RAW-NEXT:       [  0, _ZN8Derived14funcEii,        50 ] (25.00%)
-// RAW-NEXT:       [  0, {{.*}}instrprof-vtable-value-prof.cpp;_ZN12_GLOBAL__N_18Derived24funcEii,        150 ] (75.00%)
+// RAW-NEXT:       [  0, {{.*}}lib.cpp;_ZN12_GLOBAL__N_18Derived24funcEii,        150 ] (75.00%)
 // RAW-NEXT:       [  1, _ZN8Derived1D0Ev,        250 ] (25.00%)
-// RAW-NEXT:       [  1, {{.*}}instrprof-vtable-value-prof.cpp;_ZN12_GLOBAL__N_18Derived2D0Ev,        750 ] (75.00%)
+// RAW-NEXT:       [  1, {{.*}}lib.cpp;_ZN12_GLOBAL__N_18Derived2D0Ev,        750 ] (75.00%)
 // RAW-NEXT:  VTable Results:
 // RAW-NEXT:       [  0, _ZTV8Derived1,        50 ] (25.00%)
-// RAW-NEXT:       [  0, {{.*}}instrprof-vtable-value-prof.cpp;_ZTVN12_GLOBAL__N_18Derived2E,        150 ] (75.00%)
+// RAW-NEXT:       [  0, {{.*}}lib.cpp;_ZTVN12_GLOBAL__N_18Derived2E,        150 ] (75.00%)
 // RAW-NEXT:       [  1, _ZTV8Derived1,        250 ] (25.00%)
-// RAW-NEXT:       [  1, {{.*}}instrprof-vtable-value-prof.cpp;_ZTVN12_GLOBAL__N_18Derived2E,        750 ] (75.00%)
+// RAW-NEXT:       [  1, {{.*}}lib.cpp;_ZTVN12_GLOBAL__N_18Derived2E,        750 ] (75.00%)
 // INDEXED:     Indirect Target Results:
-// INDEXED-NEXT:         [  0, {{.*}}instrprof-vtable-value-prof.cpp;_ZN12_GLOBAL__N_18Derived24funcEii,        150 ] (75.00%)
+// INDEXED-NEXT:         [  0, {{.*}}lib.cpp;_ZN12_GLOBAL__N_18Derived24funcEii,        150 ] (75.00%)
 // INDEXED-NEXT:         [  0, _ZN8Derived14funcEii,        50 ] (25.00%)
-// INDEXED-NEXT:         [  1, {{.*}}instrprof-vtable-value-prof.cpp;_ZN12_GLOBAL__N_18Derived2D0Ev,        750 ] (75.00%)
+// INDEXED-NEXT:         [  1, {{.*}}lib.cpp;_ZN12_GLOBAL__N_18Derived2D0Ev,        750 ] (75.00%)
 // INDEXED-NEXT:         [  1, _ZN8Derived1D0Ev,        250 ] (25.00%)
 // INDEXED-NEXT:     VTable Results:
-// INDEXED-NEXT:         [  0, {{.*}}instrprof-vtable-value-prof.cpp;_ZTVN12_GLOBAL__N_18Derived2E,        150 ] (75.00%)
+// INDEXED-NEXT:         [  0, {{.*}}lib.cpp;_ZTVN12_GLOBAL__N_18Derived2E,        150 ] (75.00%)
 // INDEXED-NEXT:         [  0, _ZTV8Derived1,        50 ] (25.00%)
-// INDEXED-NEXT:         [  1, {{.*}}instrprof-vtable-value-prof.cpp;_ZTVN12_GLOBAL__N_18Derived2E,        750 ] (75.00%)
+// INDEXED-NEXT:         [  1, {{.*}}lib.cpp;_ZTVN12_GLOBAL__N_18Derived2E,        750 ] (75.00%)
 // INDEXED-NEXT:         [  1, _ZTV8Derived1,        250 ] (25.00%)
 // COMMON: Instrumentation level: IR  entry_first = 0
 // COMMON-NEXT: Functions shown: 1
@@ -94,27 +94,27 @@
 // ICTEXT: # NumValueSites:
 // ICTEXT: 2
 // ICTEXT: 2
-// ICTEXT: {{.*}}instrprof-vtable-value-prof.cpp;_ZN12_GLOBAL__N_18Derived24funcEii:150
+// ICTEXT: {{.*}}lib.cpp;_ZN12_GLOBAL__N_18Derived24funcEii:150
 // ICTEXT: _ZN8Derived14funcEii:50
 // ICTEXT: 2
-// ICTEXT: {{.*}}instrprof-vtable-value-prof.cpp;_ZN12_GLOBAL__N_18Derived2D0Ev:750
+// ICTEXT: {{.*}}lib.cpp;_ZN12_GLOBAL__N_18Derived2D0Ev:750
 // ICTEXT: _ZN8Derived1D0Ev:250
 // ICTEXT: # ValueKind = IPVK_VTableTarget:
 // ICTEXT: 2
 // ICTEXT: # NumValueSites:
 // ICTEXT: 2
 // ICTEXT: 2
-// ICTEXT: {{.*}}instrprof-vtable-value-prof.cpp;_ZTVN12_GLOBAL__N_18Derived2E:150
+// ICTEXT: {{.*}}lib.cpp;_ZTVN12_GLOBAL__N_18Derived2E:150
 // ICTEXT: _ZTV8Derived1:50
 // ICTEXT: 2
-// ICTEXT: {{.*}}instrprof-vtable-value-prof.cpp;_ZTVN12_GLOBAL__N_18Derived2E:750
+// ICTEXT: {{.*}}lib.cpp;_ZTVN12_GLOBAL__N_18Derived2E:750
 // ICTEXT: _ZTV8Derived1:250
 
 // When vtable value profiles exist, pgo-instr-use pass should annotate them
 // even if `-enable-vtable-value-profiling` is not explicitly on.
 // RUN: %clangxx -m64 -fprofile-use=test.profdata -fuse-ld=lld -O2 \
 // RUN:   -mllvm -print-after=pgo-instr-use -mllvm -filter-print-funcs=main \
-// RUN:   -mllvm -print-module-scope %s 2>&1 | FileCheck %s --check-prefix=ANNOTATE
+// RUN:   -mllvm -print-module-scope lib.cpp main.cpp 2>&1 | FileCheck %s --check-prefix=ANNOTATE
 
 // ANNOTATE-NOT: Inconsistent number of value sites
 // ANNOTATE: !{!"VP", i32 2
@@ -123,7 +123,7 @@
 // if `-icp-max-num-vtables` is set to zero.
 // RUN: %clangxx -m64 -fprofile-use=test.profdata -fuse-ld=lld -O2 \
 // RUN:   -mllvm -icp-max-num-vtables=0 -mllvm -print-after=pgo-instr-use \
-// RUN:   -mllvm -filter-print-funcs=main -mllvm -print-module-scope %s 2>&1 | \
+// RUN:   -mllvm -filter-print-funcs=main -mllvm -print-module-scope lib.cpp main.cpp 2>&1 | \
 // RUN:   FileCheck %s --check-prefix=OMIT
 
 // OMIT: Inconsistent number of value sites
@@ -145,26 +145,26 @@
 // RUN:    -Wl,-plugin-opt,-import-assume-unique-local \
 // RUN:    -Wl,-mllvm,-enable-vtable-profile-use -Rpass=pgo-icall-prom \
 // RUN:    -Wl,-mllvm,-print-after=pgo-icall-prom \
-// RUN:    -Wl,-mllvm,-filter-print-funcs=main %s 2>&1 \
+// RUN:    -Wl,-mllvm,-filter-print-funcs=main lib.cpp main.cpp 2>&1 \
 // RUN:    | FileCheck %s --check-prefixes=REMARK,IR --implicit-check-not="!VP"
 
 // For the indirect call site `ptr->func`
-// REMARK: instrprof-vtable-value-prof.cpp:240:19: Promote indirect call to _ZN12_GLOBAL__N_18Derived24funcEii with count 150 out of 200, sink 1 instruction(s) and compare 1 vtable(s): {_ZTVN12_GLOBAL__N_18Derived2E}
-// REMARK: instrprof-vtable-value-prof.cpp:240:19: Promote indirect call to _ZN8Derived14funcEii with count 50 out of 50, sink 1 instruction(s) and compare 1 vtable(s): {_ZTV8Derived1}
+// REMARK: main.cpp:10:19: Promote indirect call to _ZN12_GLOBAL__N_18Derived24funcEii.llvm.{{.*}} with count 150 out of 200, sink 1 instruction(s) and compare 1 vtable(s): {_ZTVN12_GLOBAL__N_18Derived2E.llvm.{{.*}}}
+// REMARK: main.cpp:10:19: Promote indirect call to _ZN8Derived14funcEii with count 50 out of 50, sink 1 instruction(s) and compare 1 vtable(s): {_ZTV8Derived1}
 //
 // For the indirect call site `delete ptr`
-// REMARK: instrprof-vtable-value-prof.cpp:242:5: Promote indirect call to _ZN12_GLOBAL__N_18Derived2D0Ev with count 750 out of 1000, sink 2 instruction(s) and compare 1 vtable(s): {_ZTVN12_GLOBAL__N_18Derived2E}
-// REMARK: instrprof-vtable-value-prof.cpp:242:5: Promote indirect call to _ZN8Derived1D0Ev with count 250 out of 250, sink 2 instruction(s) and compare 1 vtable(s): {_ZTV8Derived1}
+// REMARK: main.cpp:12:5: Promote indirect call to _ZN12_GLOBAL__N_18Derived2D0Ev.llvm.{{.*}} with count 750 out of 1000, sink 2 instruction(s) and compare 1 vtable(s): {_ZTVN12_GLOBAL__N_18Derived2E.llvm.{{.*}}}
+// REMARK: main.cpp:12:5: Promote indirect call to _ZN8Derived1D0Ev with count 250 out of 250, sink 2 instruction(s) and compare 1 vtable(s): {_ZTV8Derived1}
 
 // The IR matchers for indirect callsite `ptr->func`.
 // IR-LABEL: @main
 // IR:   [[OBJ:%.*]] = {{.*}}call {{.*}} @_Z10createTypei
 // IR:   [[VTABLE:%.*]] = load ptr, ptr [[OBJ]]
-// IR:   [[CMP1:%.*]] = icmp eq ptr [[VTABLE]], getelementptr inbounds (i8, ptr @_ZTVN12_GLOBAL__N_18Derived2E, i32 16)
+// IR:   [[CMP1:%.*]] = icmp eq ptr [[VTABLE]], getelementptr inbounds (i8, ptr @_ZTVN12_GLOBAL__N_18Derived2E.llvm.{{.*}}, i32 16)
 // IR:   br i1 [[CMP1]], label %[[BB1:.*]], label %[[BB2:[a-zA-Z0-9_.]+]],
 //
 // IR: [[BB1]]:
-// IR:   [[RESBB1:%.*]] = {{.*}}call {{.*}} @_ZN12_GLOBAL__N_18Derived24funcEii
+// IR:   [[RESBB1:%.*]] = {{.*}}call {{.*}} @_ZN12_GLOBAL__N_18Derived24funcEii.llvm.{{.*}}
 // IR:   br label %[[MERGE0:[a-zA-Z0-9_.]+]]
 //
 // IR: [[BB2]]:
@@ -203,23 +203,23 @@ class Derived1 : public Base {
 
   ~Derived1() {}
 };
+
+__attribute__((noinline)) Base *createType(int a);
+
+//--- lib.cpp
+#include "lib.h"
+
 namespace {
 class Derived2 : public Base {
 public:
-  int func(int a, int b) override;
+  int func(int a, int b) override { return a * (a - b); }
 
   ~Derived2() {}
 };
 } // namespace
 
-__attribute__((noinline)) Base *createType(int a);
-
-//-- lib.cpp
-
 int Derived1::func(int a, int b) { return a * b; }
 
-int Derived2::func(int a, int b) { return a * (a - b); }
-
 Base *createType(int a) {
   Base *base = nullptr;
   if (a % 4 == 0)
@@ -230,6 +230,8 @@ Base *createType(int a) {
 }
 
 //--- main.cpp
+#include "lib.h"
+
 int main(int argc, char **argv) {
   int sum = 0;
   for (int i = 0; i < 1000; i++) {
diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp
index 839c09fa9d586..08976058fb592 100644
--- a/llvm/lib/Transforms/IPO/FunctionImport.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp
@@ -381,6 +381,10 @@ class GlobalsImporter final {
           [&](const GlobalValueSummary *RefSummary) -> bool {
         if (ImportAssumeUniqueLocal)
           return false;
+
+        errs() << "Ref VI is " << VI << "\n";
+        errs() << RefSummary->modulePath() << "\n";
+        errs() << Summary.modulePath() << "\n";
         return GlobalValue::isLocalLinkage(RefSummary->linkage()) &&
                RefSummary->modulePath() != Summary.modulePath();
       };



More information about the llvm-commits mailing list