[PR] Fdata: Escape whitespaces in symbol names

Summary:
This patch is part of preparation for golang support. The golang symbols
might have spaces in the name (for example "type..eq.[10]interface {}").
Since fdata uses spaces as a field separator such names brakes the fdata
format, so we need to escape whitespaces and backslashes in symbol names
using the backslash character.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

(cherry picked from FBD29999491)

bolt/src/DataAggregator.cpp

@@ -2201,9 +2201,8 @@ DataAggregator::writeAggregatedFile(StringRef OutputFilename) const {
       OutFile << (Loc.IsSymbol ? "4 " : "3 ");
     else
       OutFile << (Loc.IsSymbol ? "1 " : "0 ");
-    OutFile << (Loc.Name.empty() ? "[unknown]" : Loc.Name)  << " "
+    OutFile << (Loc.Name.empty() ? "[unknown]" : getEscapedName(Loc.Name))
-            << Twine::utohexstr(Loc.Offset)
+            << " " << Twine::utohexstr(Loc.Offset) << FieldSeparator;
-            << FieldSeparator;
   };
 
   uint64_t BranchValues = 0;

bolt/src/DataReader.cpp

@@ -11,10 +11,10 @@
 //
 //===----------------------------------------------------------------------===//
 
-
-#include "BinaryFunction.h"
 #include "DataReader.h"
+#include "BinaryFunction.h"
 #include "Passes/MCF.h"
+#include "Utils.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include <map>
@@ -62,10 +62,11 @@ bool hasVolatileName(const BinaryFunction &BF) {
   return false;
 }
 
-/// Return standard name of the function possibly renamed by BOLT.
+/// Return standard escaped name of the function possibly renamed by BOLT.
-StringRef normalizeName(StringRef Name) {
+std::string normalizeName(StringRef NameRef) {
   // Strip "PG." prefix used for globalized locals.
-  return Name.startswith("PG.") ? Name.substr(2) : Name;
+  NameRef = NameRef.startswith("PG.") ? NameRef.substr(2) : NameRef;
+  return getEscapedName(NameRef);
 }
 
 } // anonymous namespace
@@ -859,15 +860,31 @@ bool DataReader::checkAndConsumeNewLine() {
 }
 
 ErrorOr<StringRef> DataReader::parseString(char EndChar, bool EndNl) {
+  if (EndChar == '\\') {
+    reportError("EndChar could not be backslash");
+    return make_error_code(llvm::errc::io_error);
+  }
+
   std::string EndChars(1, EndChar);
+  EndChars.push_back('\\');
   if (EndNl)
     EndChars.push_back('\n');
-  size_t StringEnd = ParsingBuf.find_first_of(EndChars);
+
-  if (StringEnd == StringRef::npos || StringEnd == 0) {
+  size_t StringEnd = 0;
+  do {
+    StringEnd = ParsingBuf.find_first_of(EndChars, StringEnd);
+    if (StringEnd == StringRef::npos ||
+        (StringEnd == 0 && ParsingBuf[StringEnd] != '\\')) {
       reportError("malformed field");
       return make_error_code(llvm::errc::io_error);
     }
 
+    if (ParsingBuf[StringEnd] != '\\')
+      break;
+
+    StringEnd += 2;
+  } while (1);
+
   StringRef Str = ParsingBuf.substr(0, StringEnd);
 
   // If EndNl was set and nl was found instead of EndChar, do not consume the
@@ -1317,8 +1334,7 @@ fetchMapEntriesRegex(
   // Do a reverse order iteration since the name in profile has a higher chance
   // of matching a name at the end of the list.
   for (auto FI = FuncNames.rbegin(), FE = FuncNames.rend(); FI != FE; ++FI) {
-    StringRef Name = *FI;
+    std::string Name = normalizeName(*FI);
-    Name = normalizeName(Name);
     const Optional<StringRef> LTOCommonName = getLTOCommonName(Name);
     if (LTOCommonName) {
       auto I = LTOCommonNameMap.find(*LTOCommonName);

bolt/src/Passes/Instrumentation.cpp

@@ -11,6 +11,7 @@
 #include "Instrumentation.h"
 #include "ParallelUtilities.h"
 #include "RuntimeLibs/InstrumentationRuntimeLibrary.h"
+#include "Utils.h"
 #include "llvm/Support/CommandLine.h"
 #include <stack>
 
@@ -90,7 +91,7 @@ uint32_t Instrumentation::getFunctionNameIndex(const BinaryFunction &Function) {
     return Iter->second;
   size_t Idx = Summary->StringTable.size();
   FuncToStringIdx.emplace(std::make_pair(&Function, Idx));
-  Summary->StringTable.append(std::string(Function.getOneName()));
+  Summary->StringTable.append(getEscapedName(Function.getOneName()));
   Summary->StringTable.append(1, '\0');
   return Idx;
 }

bolt/src/Utils.cpp

@@ -48,6 +48,26 @@ void check_error(Error E, Twine Message) {
   });
 }
 
+std::string getEscapedName(const StringRef &Name) {
+  std::string Output = Name.str();
+  for (size_t I = 0; I < Output.size(); ++I) {
+    if (Output[I] == ' ' || Output[I] == '\\')
+      Output.insert(I++, 1, '\\');
+  }
+
+  return Output;
+}
+
+std::string getUnescapedName(const StringRef &Name) {
+  std::string Output = Name.str();
+  for (size_t I = 0; I < Output.size(); ++I) {
+    if (Output[I] == '\\')
+      Output.erase(I++, 1);
+  }
+
+  return Output;
+}
+
 Optional<uint8_t> readDWARFExpressionTargetReg(StringRef ExprBytes) {
   uint8_t Opcode = ExprBytes[0];
   if (Opcode == dwarf::DW_CFA_def_cfa_expression)

bolt/src/Utils.h

@@ -35,6 +35,12 @@ void check_error(std::error_code EC, StringRef Message);
 
 void check_error(Error E, Twine Message);
 
+/// Return the name with escaped whitespace and backslash characters
+std::string getEscapedName(const StringRef &Name);
+
+/// Return the unescaped name
+std::string getUnescapedName(const StringRef &Name);
+
 // Determines which register a given DWARF expression is being assigned to.
 // If the expression is defining the CFA, return NoneType.
 Optional<uint8_t> readDWARFExpressionTargetReg(StringRef ExprBytes);

bolt/test/CMakeLists.txt

@@ -10,6 +10,7 @@ set(BOLT_TEST_PARAMS
   )
 
 list(APPEND BOLT_TEST_DEPS
+  llc
   llvm-config
   FileCheck count not
   llvm-bolt
@@ -22,6 +23,7 @@ list(APPEND BOLT_TEST_DEPS
   llvm-strip
   llvm-dwarfdump
   llvm-mc
+  llvm-objcopy
   )
 
 add_custom_target(bolt-test-depends DEPENDS ${BOLT_TEST_DEPS})

bolt/test/X86/Inputs/fdata-escape-chars-syms.txt

@@ -0,0 +1,3 @@
+symb_w_whitespace symb whitespace
+symb_backslash_b symb backslash\
+static_symb_backslash_b static symb backslash\

bolt/test/X86/Inputs/fdata-escape-chars.txt

@@ -0,0 +1,6 @@
+# PREAGR: B #main# #static symb backslash\# 1 0
+# PREAGR: B #static symb backslash\# #symb whitespace# 1 0
+# PREAGR: B #main# #symb whitespace# 1 0
+# PREAGR: B #main# #symb backslash\# 1 0
+# PREAGR: B #main# #symb backslash\# 1 0
+# PREAGR: B #symb backslash\# #symb whitespace# 2 0

bolt/test/X86/fdata-escape-chars.ll

@@ -0,0 +1,101 @@
+@var = dso_local global i32 0, align 4
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local void @symb_w_whitespace() #0 {
+  store volatile i32 1, i32* @var, align 4
+  ret void
+}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local void @symb_backslash_b() #0 {
+  call void @symb_w_whitespace()
+  store volatile i32 2, i32* @var, align 4
+  ret void
+}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define dso_local i32 @main() #0 {
+  %1 = alloca i32, align 4
+  %2 = alloca i32, align 4
+  store i32 0, i32* %1, align 4
+  call void @static_symb_backslash_b()
+  call void @symb_w_whitespace()
+  store i32 0, i32* %2, align 4
+  br label %3
+
+3:                                                ; preds = %7, %0
+  %4 = load i32, i32* %2, align 4
+  %5 = icmp slt i32 %4, 2
+  br i1 %5, label %6, label %10
+
+6:                                                ; preds = %3
+  call void @symb_backslash_b()
+  br label %7
+
+7:                                                ; preds = %6
+  %8 = load i32, i32* %2, align 4
+  %9 = add nsw i32 %8, 1
+  store i32 %9, i32* %2, align 4
+  br label %3
+
+10:                                               ; preds = %3
+  %11 = load i32, i32* %1, align 4
+  ret i32 %11
+}
+
+; Function Attrs: noinline nounwind optnone uwtable
+define internal void @static_symb_backslash_b() #0 {
+  call void @symb_w_whitespace()
+  store volatile i32 3, i32* @var, align 4
+  ret void
+}
+
+; REQUIRES: system-linux
+
+; RUN: llc %s -o %t.s
+; RUN: %host_cc %cflags -O0 %t.s -o %t.exe -Wl,-q
+; RUN: llvm-objcopy --redefine-syms=%p/Inputs/fdata-escape-chars-syms.txt %t.exe
+;
+; RUN: llvm-bolt %t.exe -o %t.exe.instrumented -instrument  \
+; RUN:   -instrumentation-file=%t.fdata
+; RUN: %t.exe.instrumented
+; RUN: cat %t.fdata | \
+; RUN:   FileCheck --check-prefix="FDATA_CHECK" %s
+; RUN: llvm-bolt %t.exe -o %t.fdata.exe -data %t.fdata -print-finalized | \
+; RUN:   FileCheck --check-prefix="INSTR_CHECK" %s
+;
+; RUN: link_fdata %p/Inputs/fdata-escape-chars.txt %t.exe %t.pre "PREAGR"
+; RUN: perf2bolt %t.exe -o %t.pre.fdata -pa -p %t.pre
+; RUN: cat %t.pre.fdata | FileCheck --check-prefix="PREAGR_FDATA_CHECK" %s
+; RUN: llvm-bolt %t.exe -o %t.pre.fdata.exe -data %t.pre.fdata -print-finalized | \
+; RUN:   FileCheck --check-prefix="PREAGR_CHECK" %s
+
+; FDATA_CHECK: 1 symb\ backslash\\ {{([[:xdigit:]]+)}} 1 symb\ whitespace 0 0 2
+; FDATA_CHECK: 1 main {{([[:xdigit:]]+)}} 1 symb\ whitespace 0 0 1
+; FDATA_CHECK: 1 main {{([[:xdigit:]]+)}} 1 symb\ backslash\\ 0 0 2
+
+; INSTR_CHECK: Binary Function "symb whitespace"
+; INSTR_CHECK: Exec Count  : 4
+; INSTR_CHECK: Binary Function "symb backslash\"
+; INSTR_CHECK: Exec Count  : 2
+; INSTR_CHECK: {{([[:xdigit:]]+)}}:   callq   "symb whitespace" # Count: 2
+; INSTR_CHECK: Binary Function "main"
+; INSTR_CHECK: Exec Count  : 1
+; INSTR_CHECK: {{([[:xdigit:]]+)}}:   callq   "symb whitespace" # Count: 1
+; INSTR_CHECK: {{([[:xdigit:]]+)}}:   callq   "symb backslash\" # Count: 2
+; INSTR_CHECK: Binary Function "static symb backslash\/1(*2)"
+; INSTR_CHECK: Exec Count  : 1
+; INSTR_CHECK: {{([[:xdigit:]]+)}}:   callq   "symb whitespace" # Count: 1
+
+; PREAGR_FDATA_CHECK: 1 symb\ backslash\\ 0 1 symb\ whitespace 0 0 2
+; PREAGR_FDATA_CHECK: 1 main 0 1 static\ symb\ backslash\\/1 0 0 1
+; PREAGR_FDATA_CHECK: 1 main 0 1 symb\ whitespace 0 0 1
+; PREAGR_FDATA_CHECK: 1 main 0 1 symb\ backslash\\ 0 0 2
+; PREAGR_FDATA_CHECK: 1 static\ symb\ backslash\\/1 0 1 symb\ whitespace 0 0 1
+
+; PREAGR_CHECK: Binary Function "symb whitespace"
+; PREAGR_CHECK-DAG: Exec Count  : 4
+; PREAGR_CHECK: Binary Function "symb backslash\"
+; PREAGR_CHECK-DAG: Exec Count  : 2
+; PREAGR_CHECK: Binary Function "static symb backslash\/1(*2)"
+; PREAGR_CHECK-DAG: Exec Count  : 1

bolt/test/link_fdata.sh

@@ -7,7 +7,7 @@ mapfile -t symbols < <(nm --defined-only "$2")
 
 for line in "${symbols[@]}"; do
     val=$(echo $line | cut -d' ' -f1)
-    symname=$(echo $line | cut -d' ' -f3)
+    symname=$(echo $line | awk '{ $1=$2=""; print $0 }' | sed 's/^[ \t]*//')
     if [ -z "$symname" ]; then
         continue
     fi

bolt/test/lit.cfg.py

@@ -51,6 +51,7 @@ tool_dirs = [config.llvm_tools_dir,
              config.test_source_root]
 
 tools = [
+    ToolSubst('llc', unresolved='fatal'),
     ToolSubst('llvm-dwarfdump', unresolved='fatal'),
     ToolSubst('llvm-bolt', unresolved='fatal'),
     ToolSubst('perf2bolt', unresolved='fatal'),
@@ -58,6 +59,7 @@ tools = [
     ToolSubst('llvm-mc', unresolved='fatal'),
     ToolSubst('llvm-nm', unresolved='fatal'),
     ToolSubst('llvm-objdump', unresolved='fatal'),
+    ToolSubst('llvm-objcopy', unresolved='fatal'),
     ToolSubst('llvm-strip', unresolved='fatal'),
     ToolSubst('link_fdata', command=FindTool('link_fdata.sh'), unresolved='fatal'),
 ]