[PGO] Initialize GCOV Writeout and Reset Functions in the Runtime on AIX

clang/test/CodeGen/code-coverage.c

@@ -3,12 +3,18 @@
 /// 4.7 enables cfg_checksum.
 /// 4.8 (default, compatible with gcov 7) emits the exit block the second.
 // RUN: rm -rf %t && mkdir %t && cd %t
-// RUN: %clang_cc1 -emit-llvm -disable-red-zone -coverage-data-file=/dev/null -coverage-version='304*' %s -o - | \
-// RUN:   FileCheck --check-prefixes=CHECK,304 %s
-// RUN: %clang_cc1 -emit-llvm -disable-red-zone -coverage-data-file=/dev/null -coverage-version='407*' %s -o - | \
-// RUN:   FileCheck --check-prefixes=CHECK,407 %s
-// RUN: %clang_cc1 -emit-llvm -disable-red-zone -coverage-data-file=/dev/null %s -o - | \
-// RUN:   FileCheck --check-prefixes=CHECK,408 %s
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -disable-red-zone -coverage-data-file=/dev/null -coverage-version='304*' %s -o - | \
+// RUN:   FileCheck --check-prefixes=CHECK,CHECK-CTOR-INIT,304 %s
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -disable-red-zone -coverage-data-file=/dev/null -coverage-version='407*' %s -o - | \
+// RUN:   FileCheck --check-prefixes=CHECK,CHECK-CTOR-INIT,407 %s
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm -disable-red-zone -coverage-data-file=/dev/null %s -o - | \
+// RUN:   FileCheck --check-prefixes=CHECK,CHECK-CTOR-INIT,408 %s
+// RUN: %clang_cc1 -triple powerpc64-ibm-aix -emit-llvm -disable-red-zone -coverage-data-file=/dev/null -coverage-version='304*' %s -o - | \
+// RUN:   FileCheck --check-prefixes=CHECK,CHECK-RT-INIT,304 %s
+// RUN: %clang_cc1 -triple powerpc64-ibm-aix -emit-llvm -disable-red-zone -coverage-data-file=/dev/null -coverage-version='407*' %s -o - | \
+// RUN:   FileCheck --check-prefixes=CHECK,CHECK-RT-INIT,407 %s
+// RUN: %clang_cc1 -triple powerpc64-ibm-aix -emit-llvm -disable-red-zone -coverage-data-file=/dev/null %s -o - | \
+// RUN:   FileCheck --check-prefixes=CHECK,CHECK-RT-INIT,408 %s
 
 // RUN: %clang_cc1 -emit-llvm -disable-red-zone -coverage-notes-file=aaa.gcno -coverage-data-file=bbb.gcda -debug-info-kind=limited -dwarf-version=4 %s -o - | FileCheck %s --check-prefix GCOV_FILE_INFO
 
@@ -49,10 +55,13 @@ int test2(int b) {
 /// 0x3430382a '4' '0' '8' '*'
 // 408-SAME: i32 875575338
 
+// Check for gcov initialization function pointers.
+// CHECK-RT-INIT: @__llvm_covinit_functions = private constant { ptr, ptr } { ptr @__llvm_gcov_writeout, ptr @__llvm_gcov_reset }, section "__llvm_covinit"
+
 // Check that the noredzone flag is set on the generated functions.
 
 // CHECK: void @__llvm_gcov_writeout() unnamed_addr [[NRZ:#[0-9]+]]
-// CHECK: void @__llvm_gcov_init() unnamed_addr [[NRZ]]
+// CHECK-CTOR-INIT: void @__llvm_gcov_init() unnamed_addr [[NRZ]]
 
 // CHECK: attributes [[NRZ]] = { {{.*}}noredzone{{.*}} }
 

compiler-rt/include/profile/InstrProfData.inc

@@ -303,6 +303,18 @@ COVMAP_HEADER(uint32_t, Int32Ty, Version, \
 #undef COVMAP_HEADER
 /* COVMAP_HEADER end.  */
 
+/* COVINIT_FUNC start */
+#ifndef COVINIT_FUNC
+#define COVINIT_FUNC(Type, LLVMType, Name, Initializer)
+#else
+#define INSTR_PROF_DATA_DEFINED
+#endif
+COVINIT_FUNC(IntPtrT, llvm::PointerType::getUnqual(Ctx), WriteoutFunction, \
+             WriteoutF)
+COVINIT_FUNC(IntPtrT, llvm::PointerType::getUnqual(Ctx), ResetFunction, \
+             ResetF)
+#undef COVINIT_FUNC
+/* COVINIT_FUNC end */
 
 #ifdef INSTR_PROF_SECT_ENTRY
 #define INSTR_PROF_DATA_DEFINED
@@ -345,6 +357,9 @@ INSTR_PROF_SECT_ENTRY(IPSK_covdata, \
 INSTR_PROF_SECT_ENTRY(IPSK_covname, \
                       INSTR_PROF_QUOTE(INSTR_PROF_COVNAME_COMMON), \
                       INSTR_PROF_COVNAME_COFF, "__LLVM_COV,")
+INSTR_PROF_SECT_ENTRY(IPSK_covinit, \
+                      INSTR_PROF_QUOTE(INSTR_PROF_COVINIT_COMMON), \
+                      INSTR_PROF_COVINIT_COFF, "__LLVM_COV,")
 
 #undef INSTR_PROF_SECT_ENTRY
 #endif
@@ -761,6 +776,8 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 #define INSTR_PROF_COVDATA_COMMON __llvm_covdata
 #define INSTR_PROF_COVNAME_COMMON __llvm_covnames
 #define INSTR_PROF_ORDERFILE_COMMON __llvm_orderfile
+#define INSTR_PROF_COVINIT_COMMON __llvm_covinit
+
 /* Windows section names. Because these section names contain dollar characters,
  * they must be quoted.
  */
@@ -781,6 +798,10 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 #define INSTR_PROF_COVNAME_COFF ".lcovn"
 #define INSTR_PROF_ORDERFILE_COFF ".lorderfile$M"
 
+// FIXME: Placeholder for Windows. Windows currently does not initialize
+// the GCOV functions in the runtime.
+#define INSTR_PROF_COVINIT_COFF ".lcovd$M"
+
 #ifdef _WIN32
 /* Runtime section names and name strings.  */
 #define INSTR_PROF_DATA_SECT_NAME INSTR_PROF_DATA_COFF
@@ -800,6 +821,7 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 #define INSTR_PROF_COVDATA_SECT_NAME INSTR_PROF_COVDATA_COFF
 #define INSTR_PROF_COVNAME_SECT_NAME INSTR_PROF_COVNAME_COFF
 #define INSTR_PROF_ORDERFILE_SECT_NAME INSTR_PROF_ORDERFILE_COFF
+#define INSTR_PROF_COVINIT_SECT_NAME INSTR_PROF_COVINIT_COFF
 #else
 /* Runtime section names and name strings.  */
 #define INSTR_PROF_DATA_SECT_NAME INSTR_PROF_QUOTE(INSTR_PROF_DATA_COMMON)
@@ -821,6 +843,7 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 /* Order file instrumentation. */
 #define INSTR_PROF_ORDERFILE_SECT_NAME                                         \
   INSTR_PROF_QUOTE(INSTR_PROF_ORDERFILE_COMMON)
+#define INSTR_PROF_COVINIT_SECT_NAME INSTR_PROF_QUOTE(INSTR_PROF_COVINIT_COMMON)
 #endif
 
 #define INSTR_PROF_ORDERFILE_BUFFER_NAME _llvm_order_file_buffer

compiler-rt/lib/profile/GCDAProfiling.c

@@ -624,6 +624,25 @@ void llvm_gcov_init(fn_ptr wfn, fn_ptr rfn) {
   }
 }
 
+#if defined(_AIX)
+COMPILER_RT_VISIBILITY __attribute__((constructor)) void
+__llvm_profile_gcov_initialize() {
+  const __llvm_gcov_init_func_struct *InitFuncStart =
+      __llvm_profile_begin_covinit();
+  const __llvm_gcov_init_func_struct *InitFuncEnd =
+      __llvm_profile_end_covinit();
+
+  for (const __llvm_gcov_init_func_struct *Ptr = InitFuncStart;
+       Ptr != InitFuncEnd; ++Ptr) {
+    fn_ptr wfn = (fn_ptr)Ptr->WriteoutFunction;
+    fn_ptr rfn = (fn_ptr)Ptr->ResetFunction;
+    if (!(wfn && rfn))
+      continue;
+    llvm_gcov_init(wfn, rfn);
+  }
+}
+#endif
+
 void __gcov_dump(void) {
   for (struct fn_node *f = writeout_fn_list.head; f; f = f->next)
     f->fn();

compiler-rt/lib/profile/InstrProfiling.h

@@ -54,6 +54,12 @@ typedef struct COMPILER_RT_ALIGNAS(INSTR_PROF_DATA_ALIGNMENT) VTableProfData {
 #include "profile/InstrProfData.inc"
 } VTableProfData;
 
+typedef struct COMPILER_RT_ALIGNAS(INSTR_PROF_DATA_ALIGNMENT)
+    __llvm_gcov_init_func_struct {
+#define COVINIT_FUNC(Type, LLVMType, Name, Initializer) Type Name;
+#include "profile/InstrProfData.inc"
+} __llvm_gcov_init_func_struct;
+
 /*!
  * \brief Return 1 if profile counters are continuously synced to the raw
  * profile via an mmap(). This is in contrast to the default mode, in which
@@ -208,6 +214,9 @@ void __llvm_profile_initialize_file(void);
 /*! \brief Initialize the profile runtime. */
 void __llvm_profile_initialize(void);
 
+/*! \brief Initialize the gcov profile runtime. */
+void __llvm_profile_gcov_initialize(void);
+
 /*!
  * \brief Return path prefix (excluding the base filename) of the profile data.
  * This is useful for users using \c -fprofile-generate=./path_prefix who do
@@ -324,4 +333,6 @@ COMPILER_RT_VISIBILITY extern uint64_t
  */
 extern char INSTR_PROF_PROFILE_NAME_VAR[1]; /* __llvm_profile_filename. */
 
+const __llvm_gcov_init_func_struct *__llvm_profile_begin_covinit();
+const __llvm_gcov_init_func_struct *__llvm_profile_end_covinit();
 #endif /* PROFILE_INSTRPROFILING_H_ */

compiler-rt/lib/profile/InstrProfilingPlatformAIX.c

@@ -202,6 +202,8 @@ static int dummy_vname[0] COMPILER_RT_SECTION(
     COMPILER_RT_SEG INSTR_PROF_VNAME_SECT_NAME);
 static int dummy_vtab[0] COMPILER_RT_SECTION(
     COMPILER_RT_SEG INSTR_PROF_VTAB_SECT_NAME);
+static int dummy_covinit_funcs[0] COMPILER_RT_SECTION(
+    COMPILER_RT_SEG INSTR_PROF_COVINIT_SECT_NAME);
 
 // To avoid GC'ing of the dummy variables by the linker, reference them in an
 // array and reference the array in the runtime registration code
@@ -214,7 +216,8 @@ COMPILER_RT_VISIBILITY
 void *__llvm_profile_keep[] = {(void *)&dummy_cnts,  (void *)&dummy_bits,
                                (void *)&dummy_data,  (void *)&dummy_name,
                                (void *)&dummy_vnds,  (void *)&dummy_orderfile,
-                               (void *)&dummy_vname, (void *)&dummy_vtab};
+                               (void *)&dummy_vname, (void *)&dummy_vtab,
+                               (void *)&dummy_covinit_funcs};
 #ifdef __GNUC__
 #pragma GCC diagnostic pop
 #endif

compiler-rt/lib/profile/InstrProfilingPlatformLinux.c

@@ -35,6 +35,8 @@
 #define PROF_ORDERFILE_START INSTR_PROF_SECT_START(INSTR_PROF_ORDERFILE_COMMON)
 #define PROF_VNODES_START INSTR_PROF_SECT_START(INSTR_PROF_VNODES_COMMON)
 #define PROF_VNODES_STOP INSTR_PROF_SECT_STOP(INSTR_PROF_VNODES_COMMON)
+#define PROF_COVINIT_START INSTR_PROF_SECT_START(INSTR_PROF_COVINIT_COMMON)
+#define PROF_COVINIT_STOP INSTR_PROF_SECT_STOP(INSTR_PROF_COVINIT_COMMON)
 
 /* Declare section start and stop symbols for various sections
  * generated by compiler instrumentation.
@@ -56,6 +58,10 @@ extern char PROF_NAME_START COMPILER_RT_VISIBILITY COMPILER_RT_WEAK;
 extern char PROF_NAME_STOP COMPILER_RT_VISIBILITY COMPILER_RT_WEAK;
 extern ValueProfNode PROF_VNODES_START COMPILER_RT_VISIBILITY COMPILER_RT_WEAK;
 extern ValueProfNode PROF_VNODES_STOP COMPILER_RT_VISIBILITY COMPILER_RT_WEAK;
+extern __llvm_gcov_init_func_struct PROF_COVINIT_START COMPILER_RT_VISIBILITY
+    COMPILER_RT_WEAK;
+extern __llvm_gcov_init_func_struct PROF_COVINIT_STOP COMPILER_RT_VISIBILITY
+    COMPILER_RT_WEAK;
 
 COMPILER_RT_VISIBILITY const __llvm_profile_data *
 __llvm_profile_begin_data(void) {
@@ -110,6 +116,16 @@ COMPILER_RT_VISIBILITY ValueProfNode *__llvm_profile_end_vnodes(void) {
 COMPILER_RT_VISIBILITY ValueProfNode *CurrentVNode = &PROF_VNODES_START;
 COMPILER_RT_VISIBILITY ValueProfNode *EndVNode = &PROF_VNODES_STOP;
 
+COMPILER_RT_VISIBILITY const __llvm_gcov_init_func_struct *
+__llvm_profile_begin_covinit() {
+  return &PROF_COVINIT_START;
+}
+
+COMPILER_RT_VISIBILITY const __llvm_gcov_init_func_struct *
+__llvm_profile_end_covinit() {
+  return &PROF_COVINIT_STOP;
+}
+
 #ifdef NT_GNU_BUILD_ID
 static size_t RoundUp(size_t size, size_t align) {
   return (size + align - 1) & ~(align - 1);

compiler-rt/test/profile/AIX/gcov-undef-sym.test

@@ -0,0 +1,52 @@
+// The undefined symbol should not cause link errors, and we should
+// obtain the expected coverage report.
+
+// Test the --coverage option.
+RUN: rm -rf %t0 && split-file %s %t0 && cd %t0
+RUN: %clang bar.c main.c undef.c --coverage -c
+RUN: ar -X32_64 -rv libfoo.a undef.o bar.o
+RUN: %clang main.o -L. -lfoo --coverage -o main.exe
+RUN: %run ./main.exe
+RUN: llvm-cov gcov -t main.gcda |  FileCheck --check-prefix=MAIN %s
+RUN: llvm-cov gcov -t bar.gcda |  FileCheck --check-prefix=BAR %s
+
+// Test the pgogen -fprofile-arcs -ftest-coverage option combination.
+RUN: rm -rf %t1 && split-file %s %t1 && cd %t1
+RUN: %clang_pgogen bar.c main.c undef.c -fprofile-arcs -ftest-coverage -c
+RUN: ar -X32_64 -rv libfoo.a undef.o bar.o
+RUN: %clang_pgogen main.o -L. -lfoo -fprofile-generate -fprofile-arcs -ftest-coverage -o main.exe
+RUN: %run ./main.exe
+RUN: llvm-cov gcov -t main.gcda |  FileCheck --check-prefix=MAIN %s
+RUN: llvm-cov gcov -t bar.gcda |  FileCheck --check-prefix=BAR %s
+
+// Test the pgogen -Wl,-bcdtors:mbr option combination.
+RUN: rm -rf %t2 && split-file %s %t2 && cd %t2
+RUN: %clang_pgogen bar.c main.c undef.c -fprofile-arcs -ftest-coverage -c
+RUN: ar -X32_64 -rv libfoo.a undef.o bar.o
+RUN: %clang_pgogen main.o -L. -lfoo -fprofile-generate -fprofile-arcs -ftest-coverage -Wl,-bcdtors:mbr -o main.exe
+RUN: %run ./main.exe
+RUN: llvm-cov gcov -t main.gcda |  FileCheck --check-prefix=MAIN %s
+RUN: llvm-cov gcov -t bar.gcda |  FileCheck --check-prefix=BAR %s
+
+MAIN:        1:    2:int main() {
+MAIN:        1:    3:  return bar();
+BAR:         1:    1:int bar() {
+BAR:         1:    2:  return 0;
+
+//--- main.c
+int bar();
+int main() {
+  return bar();
+}
+
+
+//--- bar.c
+int bar() {
+  return 0;
+}
+
+//--- undef.c
+void undef_func();
+void foo() {
+  undef_func();
+}

llvm/include/llvm/ProfileData/InstrProfData.inc

@@ -303,6 +303,18 @@ COVMAP_HEADER(uint32_t, Int32Ty, Version, \
 #undef COVMAP_HEADER
 /* COVMAP_HEADER end.  */
 
+/* COVINIT_FUNC start */
+#ifndef COVINIT_FUNC
+#define COVINIT_FUNC(Type, LLVMType, Name, Initializer)
+#else
+#define INSTR_PROF_DATA_DEFINED
+#endif
+COVINIT_FUNC(IntPtrT, llvm::PointerType::getUnqual(Ctx), WriteoutFunction, \
+             WriteoutF)
+COVINIT_FUNC(IntPtrT, llvm::PointerType::getUnqual(Ctx), ResetFunction, \
+             ResetF)
+#undef COVINIT_FUNC
+/* COVINIT_FUNC end */
 
 #ifdef INSTR_PROF_SECT_ENTRY
 #define INSTR_PROF_DATA_DEFINED
@@ -345,6 +357,9 @@ INSTR_PROF_SECT_ENTRY(IPSK_covdata, \
 INSTR_PROF_SECT_ENTRY(IPSK_covname, \
                       INSTR_PROF_QUOTE(INSTR_PROF_COVNAME_COMMON), \
                       INSTR_PROF_COVNAME_COFF, "__LLVM_COV,")
+INSTR_PROF_SECT_ENTRY(IPSK_covinit, \
+                      INSTR_PROF_QUOTE(INSTR_PROF_COVINIT_COMMON), \
+                      INSTR_PROF_COVINIT_COFF, "__LLVM_COV,")
 
 #undef INSTR_PROF_SECT_ENTRY
 #endif
@@ -761,6 +776,8 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 #define INSTR_PROF_COVDATA_COMMON __llvm_covdata
 #define INSTR_PROF_COVNAME_COMMON __llvm_covnames
 #define INSTR_PROF_ORDERFILE_COMMON __llvm_orderfile
+#define INSTR_PROF_COVINIT_COMMON __llvm_covinit
+
 /* Windows section names. Because these section names contain dollar characters,
  * they must be quoted.
  */
@@ -781,6 +798,10 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 #define INSTR_PROF_COVNAME_COFF ".lcovn"
 #define INSTR_PROF_ORDERFILE_COFF ".lorderfile$M"
 
+// FIXME: Placeholder for Windows. Windows currently does not initialize
+// the GCOV functions in the runtime.
+#define INSTR_PROF_COVINIT_COFF ".lcovd$M"
+
 #ifdef _WIN32
 /* Runtime section names and name strings.  */
 #define INSTR_PROF_DATA_SECT_NAME INSTR_PROF_DATA_COFF
@@ -800,6 +821,7 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 #define INSTR_PROF_COVDATA_SECT_NAME INSTR_PROF_COVDATA_COFF
 #define INSTR_PROF_COVNAME_SECT_NAME INSTR_PROF_COVNAME_COFF
 #define INSTR_PROF_ORDERFILE_SECT_NAME INSTR_PROF_ORDERFILE_COFF
+#define INSTR_PROF_COVINIT_SECT_NAME INSTR_PROF_COVINIT_COFF
 #else
 /* Runtime section names and name strings.  */
 #define INSTR_PROF_DATA_SECT_NAME INSTR_PROF_QUOTE(INSTR_PROF_DATA_COMMON)
@@ -821,6 +843,7 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 /* Order file instrumentation. */
 #define INSTR_PROF_ORDERFILE_SECT_NAME                                         \
   INSTR_PROF_QUOTE(INSTR_PROF_ORDERFILE_COMMON)
+#define INSTR_PROF_COVINIT_SECT_NAME INSTR_PROF_QUOTE(INSTR_PROF_COVINIT_COMMON)
 #endif
 
 #define INSTR_PROF_ORDERFILE_BUFFER_NAME _llvm_order_file_buffer

llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp

@@ -290,6 +290,8 @@ class PPCAIXAsmPrinter : public PPCAsmPrinter {
 
   void emitPGORefs(Module &M);
 
+  void emitGCOVRefs();
+
   void emitEndOfAsmFile(Module &) override;
 
   void emitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const override;
@@ -2962,13 +2964,39 @@ void PPCAIXAsmPrinter::emitPGORefs(Module &M) {
   }
 }
 
+void PPCAIXAsmPrinter::emitGCOVRefs() {
+  if (!OutContext.hasXCOFFSection(
+          "__llvm_gcov_ctr_section",
+          XCOFF::CsectProperties(XCOFF::XMC_RW, XCOFF::XTY_SD)))
+    return;
+
+  MCSection *CtrSection = OutContext.getXCOFFSection(
+      "__llvm_gcov_ctr_section", SectionKind::getData(),
+      XCOFF::CsectProperties(XCOFF::XMC_RW, XCOFF::XTY_SD),
+      /*MultiSymbolsAllowed*/ true);
+
+  OutStreamer->switchSection(CtrSection);
+  const XCOFF::StorageMappingClass MappingClass =
+      TM.Options.XCOFFReadOnlyPointers ? XCOFF::XMC_RO : XCOFF::XMC_RW;
+  if (OutContext.hasXCOFFSection(
+          "__llvm_covinit",
+          XCOFF::CsectProperties(MappingClass, XCOFF::XTY_SD))) {
+    const char *SymbolStr = TM.Options.XCOFFReadOnlyPointers
+                                ? "__llvm_covinit[RO]"
+                                : "__llvm_covinit[RW]";
+    MCSymbol *S = OutContext.getOrCreateSymbol(SymbolStr);
+    OutStreamer->emitXCOFFRefDirective(S);
+  }
+}
+
 void PPCAIXAsmPrinter::emitEndOfAsmFile(Module &M) {
   // If there are no functions and there are no toc-data definitions in this
   // module, we will never need to reference the TOC base.
   if (M.empty() && TOCDataGlobalVars.empty())
     return;
 
   emitPGORefs(M);
+  emitGCOVRefs();
 
   // Switch to section to emit TOC base.
   OutStreamer->switchSection(getObjFileLowering().getTOCBaseSection());