Merge pull request #3946 from panzone/prototype-stack-trace

Print stack trace on halt

[PR by @Panzone, reviewed by @mppf and @GBT, merged by @mppf]

This PR extends the Chapel runtime with the ability to generate a stack
trace with the Chapel procedures names. Currently a stack trace is
generated and printed when an halt() is executed.

This feature works on linux64 (both libunwind and system) and darwin
(only system).

Future Work

* Update the testing system to ignore Stacktrace in .good files if stack
  tracing is disabled
* Update nightly testing to run with stack tracing enabled
* Consider if there is a reasonable way to simplify the paths output
* Consider more carefully the exact format of the stack trace printed
* Include libunwind in Chapel distributions

[Passed full local testing]

.gitignore

@@ -380,6 +380,8 @@ tags
 /test/runtime/kbrady/goodAllocSize.good
 /test/runtime/sungeun/chpl-env-gen.h
 /test/runtime/sungeun/chpl-env-gen.test.gen.c
+/test/runtime/panzone/stacktrace.good
+/test/runtime/panzone/fact-stacktrace.good
 
 test/separate_compilation/jturner/libclassextern2.so.a
 test/separate_compilation/jturner/libfcfunc.so.a

compiler/include/driver.h

@@ -98,6 +98,7 @@ extern const char* CHPL_REGEXP;
 extern const char* CHPL_WIDE_POINTERS;
 extern const char* CHPL_LLVM;
 extern const char* CHPL_AUX_FILESYS;
+extern const char* CHPL_UNWIND;
 
 extern bool  printPasses;
 extern FILE* printPassesFile;

compiler/include/insertLineNumbers.h

@@ -30,4 +30,6 @@ extern std::vector<std::string> gFilenameLookup;
 // Caches the location of filenames in gFilenameLookup
 extern std::map<std::string, int> gFilenameLookupCache;
 
+int getFilenameLookupPosition(std::string name);
+
 #endif //_INSERT_LINE_NUMBERS_H

compiler/main/driver.cpp

@@ -75,6 +75,7 @@ const char* CHPL_REGEXP = NULL;
 const char* CHPL_WIDE_POINTERS = NULL;
 const char* CHPL_LLVM = NULL;
 const char* CHPL_AUX_FILESYS = NULL;
+const char* CHPL_UNWIND = NULL;
 
 bool widePointersStruct;
 
@@ -948,6 +949,7 @@ static void setChapelEnvs() {
   CHPL_WIDE_POINTERS   = envMap["CHPL_WIDE_POINTERS"];
   CHPL_LLVM            = envMap["CHPL_LLVM"];
   CHPL_AUX_FILESYS     = envMap["CHPL_AUX_FILESYS"];
+  CHPL_UNWIND          = envMap["CHPL_UNWIND"];
 }
 
 static void setupChplGlobals(const char* argv0) {

compiler/passes/codegen.cpp

@@ -409,6 +409,61 @@ static void genFilenameTable() {
   genGlobalInt32(sizeName, gFilenameLookup.size());
 }
 
+//
+// This adds the Chapel symbol table to the config file
+// Our symbol table is formed by two 1-D arrays with 2 elements
+// per entry:
+//
+// chpl_funSymTable     = cname, Chapel name
+// chpl_filenumSymTable = Chapel file name index, Chapel line number
+//
+static void genUnwindSymbolTable(){
+  GenInfo *info = gGenInfo;
+  Vec<FnSymbol*> symbols;
+
+  //If CHPL_UNWIND is none we don't want any symbols in our tables
+  if(strcmp(CHPL_UNWIND, "none") != 0){
+    // Gets only user symbols
+    forv_Vec(FnSymbol, fn, gFnSymbols) {
+      if(strncmp(fn->cname, "chpl_", 5)) {
+        symbols.add(fn);
+      }
+    }
+  }
+
+  //TODO: Could have a native LLVM version, instead of relying on C to LLVM
+  if( info->cfile ) {
+    FILE* hdrfile = info->cfile;
+    bool first = true;
+
+    // Generate the cname, Chapel name table
+    fprintf(hdrfile,"\nc_string chpl_funSymTable[] = {\n");
+    forv_Vec(FnSymbol, fn, symbols) {
+      if(!first)
+        fprintf(hdrfile,",\n");
+
+      fprintf(hdrfile," \"%s\", \"%s\"", fn->cname, fn->name);
+      first = false;
+    }
+    fprintf(hdrfile,"};\n");
+
+    // Generate the filename index, linenum table
+    first = true;
+    fprintf(hdrfile,"\n\nint chpl_filenumSymTable[] = {\n");
+    forv_Vec(FnSymbol, fn, symbols) {
+      if(!first)
+        fprintf(hdrfile,",\n");
+
+      fprintf(hdrfile," %d, %d",
+        getFilenameLookupPosition(fn->fname()), fn->linenum());
+      first = false;
+    }
+    fprintf(hdrfile,"};\n");
+  }
+
+  genGlobalInt32("chpl_sizeSymTable", symbols.n * 2);
+}
+
 static int
 compareSymbol(const void* v1, const void* v2) {
   Symbol* s1 = *(Symbol* const *)v1;
@@ -625,6 +680,9 @@ static void codegen_header_compilation_config() {
     genComment("Filename Lookup Table");
     genFilenameTable();
 
+    genComment("Unwind symbol tables");
+    genUnwindSymbolTable();
+
     closeCFile(&cfgfile);
 
     gGenInfo->cfile = save_cfile;

compiler/passes/insertLineNumbers.cpp

@@ -44,7 +44,7 @@ std::vector<std::string> gFilenameLookup;
 // Caches lookups into our filename vector
 std::map<std::string, int> gFilenameLookupCache;
 
-static int getFilenameLookupPosition(std::string name) {
+int getFilenameLookupPosition(std::string name) {
   std::map<std::string, int>::iterator it = gFilenameLookupCache.find(name);
   int idx;
   if (it != gFilenameLookupCache.end()) {

make/Makefile.base

@@ -153,6 +153,7 @@ include $(THIRD_PARTY_DIR)/re2/Makefile.include
 include $(THIRD_PARTY_DIR)/llvm/Makefile.include-$(CHPL_MAKE_LLVM)
 include $(THIRD_PARTY_DIR)/chpl-venv/Makefile.include
 include $(THIRD_PARTY_DIR)/fltk/Makefile.include
+include $(THIRD_PARTY_DIR)/libunwind/Makefile.include
 
 -include $(THIRD_PARTY_DIR)/Makefile.devel.include
 

modules/internal/ChapelEnv.chpl

@@ -73,6 +73,8 @@ module ChapelEnv {
   /* See :ref:`readme-chplenv.CHPL_TIMERS` for more information. */
   param CHPL_TIMERS:string          = __primitive("get compiler variable", "CHPL_TIMERS");
 
+  param CHPL_UNWIND:string          = __primitive("get compiler variable", "CHPL_UNWIND");
+
   /* See :ref:`readme-chplenv.CHPL_MEM` for more information. */
   param CHPL_MEM:string             = __primitive("get compiler variable", "CHPL_MEM");
 

runtime/etc/Makefile.include

@@ -55,6 +55,7 @@ include $(CHPL_MAKE_HOME)/runtime/etc/Makefile.threads-$(CHPL_MAKE_THREADS)
 -include $(CHPL_MAKE_HOME)/runtime/etc/Makefile.tasks-$(CHPL_MAKE_TASKS)
 include $(CHPL_MAKE_HOME)/runtime/etc/Makefile.comm-$(CHPL_MAKE_COMM)
 include $(CHPL_MAKE_HOME)/runtime/etc/Makefile.mem-$(CHPL_MAKE_MEM)
+-include $(CHPL_MAKE_HOME)/runtime/etc/Makefile.unwind-$(CHPL_MAKE_UNWIND)
 include $(CHPL_MAKE_HOME)/runtime/etc/Makefile.gmp-$(CHPL_MAKE_GMP)
 -include $(CHPL_MAKE_HOME)/runtime/etc/Makefile.hwloc-$(CHPL_MAKE_HWLOC)
 include $(CHPL_MAKE_HOME)/runtime/etc/Makefile.regexp-$(CHPL_MAKE_REGEXP)

runtime/etc/Makefile.unwind-libunwind

@@ -0,0 +1,18 @@
+# Copyright 2004-2016 Cray Inc.
+# Other additional copyright holders may be indicated within.
+#
+# The entirety of this work is licensed under the Apache License,
+# Version 2.0 (the "License"); you may not use this file except
+# in compliance with the License.
+#
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+GEN_LFLAGS += -L$(LIBUNWIND_LIB_DIR)

runtime/include/chplcgfns.h

@@ -62,6 +62,7 @@ extern const char* CHPL_REGEXP;
 extern const char* CHPL_WIDE_POINTERS;
 extern const char* CHPL_LLVM;
 extern const char* CHPL_AUX_FILESYS;
+extern const char* CHPL_UNWIND;
 extern const int CHPL_STACK_CHECKS;
 extern const int CHPL_CACHE_REMOTE;
 
@@ -70,6 +71,12 @@ extern const int CHPL_CACHE_REMOTE;
 extern c_string chpl_filenameTable[];
 extern const int32_t chpl_filenameTableSize;
 
+// Lookup tables used as a symbol table by the stack unwinder for translating
+// C symbols into Chapel symbols. Defined in chpl_compilation_config.c
+extern c_string chpl_funSymTable[];
+extern int chpl_filenumSymTable[];
+extern const int32_t chpl_sizeSymTable;
+
 /* defined in main.c */
 extern char* chpl_executionCommand;
 

runtime/make/Makefile.runtime.include

@@ -97,6 +97,10 @@ endif
 GMP_INCLUDE=$(RUNTIME_ROOT)/make/Makefile.runtime.gmp-$(CHPL_MAKE_GMP)
 -include $(GMP_INCLUDE)
 
+# Add any further includes for unwind.
+UNWIND_INCLUDE=$(RUNTIME_ROOT)/make/Makefile.runtime.unwind-$(CHPL_MAKE_UNWIND)
+-include $(UNWIND_INCLUDE)
+
 # Add any further includes for HWLOC.
 HWLOC_INCLUDE=$(RUNTIME_ROOT)/make/Makefile.runtime.hwloc-$(CHPL_MAKE_HWLOC)
 -include $(HWLOC_INCLUDE)

runtime/make/Makefile.runtime.unwind-libunwind

@@ -0,0 +1,19 @@
+# Copyright 2004-2016 Cray Inc.
+# Other additional copyright holders may be indicated within.
+#
+# The entirety of this work is licensed under the Apache License,
+# Version 2.0 (the "License"); you may not use this file except
+# in compliance with the License.
+#
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+RUNTIME_DEFS += -DCHPL_UNWIND_LIBUNWIND
+RUNTIME_INCLS += -I$(LIBUNWIND_INCLUDE_DIR)

runtime/make/Makefile.runtime.unwind-system

@@ -0,0 +1,19 @@
+# Copyright 2004-2016 Cray Inc.
+# Other additional copyright holders may be indicated within.
+#
+# The entirety of this work is licensed under the Apache License,
+# Version 2.0 (the "License"); you may not use this file except
+# in compliance with the License.
+#
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+RUNTIME_DEFS += -DCHPL_UNWIND_LIBUNWIND
+

runtime/src/error.c

@@ -19,9 +19,11 @@
 
 #include "chplrt.h"
 #include "chpl-linefile-support.h"
+#include "chplcgfns.h"
 
 #include "error.h"
 #include "chplexit.h"
+#include "chpl-env.h"
 
 #include <stdarg.h>
 #include <string.h>
@@ -33,6 +35,54 @@
 #include "chpl-atomics.h"
 #endif
 
+#ifdef CHPL_UNWIND_LIBUNWIND
+// Necessary for instruct libunwind to use only the local unwind
+#define UNW_LOCAL_ONLY
+#include <libunwind.h>
+
+static void chpl_stack_unwind(void){
+  // This is just a prototype using libunwind
+  unw_cursor_t cursor;
+  unw_context_t uc;
+  unw_word_t wordValue;
+  char buffer[128];
+
+  // Check if we need to print the stack trace (default = yes)
+  if(! chpl_get_rt_env_bool("UNWIND", true)) {
+    return;
+  }
+
+  unw_getcontext(&uc);
+  unw_init_local(&cursor, &uc);
+
+  if(chpl_sizeSymTable > 0)
+    fprintf(stderr,"\nStacktrace\n\n");
+
+  // This loop does the effective stack unwind, see libunwid documentation
+  while (unw_step(&cursor) > 0) {
+    unw_get_proc_name(&cursor, buffer, sizeof(buffer), &wordValue);
+    // Since this stack trace is printed out a program exit, we do not believe
+    // it is performance sensitive. Additionally, this initial implementation
+    // favors simplicity over performance.
+    //
+    // If it becomes necessary to improve performance, this code could use be
+    // faster using one of these two strategies:
+    // 1) Use a hashtable or map to find entries in chpl_funSymTable, or
+    // 2) Emit chpl_funSymTable in sorted order and use binary search on it
+    for(int t = 0; t < chpl_sizeSymTable; t+=2 ){
+      if (!strcmp(chpl_funSymTable[t], buffer)){
+        fprintf(stderr,"%s (%s:%d)\n",
+                 chpl_funSymTable[t+1],
+                 chpl_lookupFilename(chpl_filenumSymTable[t]),
+                 chpl_filenumSymTable[t+1]);
+        break;
+      }
+    }
+  }
+  fprintf(stderr,"\n");
+}
+#endif
+
 int verbosity = 1;
 
 void chpl_warning(const char* message, int32_t lineno, int32_t filenameIdx) {
@@ -90,6 +140,11 @@ void chpl_error_explicit(const char *message, int32_t lineno,
   else
     fprintf(stderr, "error: %s", message);
   fprintf(stderr, "\n");
+
+#ifdef CHPL_UNWIND_LIBUNWIND
+  chpl_stack_unwind();
+#endif
+
   chpl_exit_any(1);
 }
 

test/compflags/albrecht/chplenv/chplenv.chpl

@@ -10,6 +10,7 @@ writeln("CHPL_GASNET_SEGMENT=",CHPL_GASNET_SEGMENT);
 writeln("CHPL_TASKS=",CHPL_TASKS);
 writeln("CHPL_LAUNCHER=",CHPL_LAUNCHER);
 writeln("CHPL_TIMERS=",CHPL_TIMERS);
+writeln("CHPL_UNWIND=",CHPL_UNWIND);
 writeln("CHPL_MEM=",CHPL_MEM);
 writeln("CHPL_MAKE=",CHPL_MAKE);
 writeln("CHPL_ATOMICS=",CHPL_ATOMICS);

test/modules/gbt/printchplenv.chpl

@@ -12,6 +12,7 @@ if CHPL_COMM != 'none' && CHPL_COMM != 'ugni' then {
 writeln('CHPL_TASKS: ', CHPL_TASKS);
 writeln('CHPL_LAUNCHER: ', CHPL_LAUNCHER);
 writeln('CHPL_TIMERS: ', CHPL_TIMERS);
+writeln('CHPL_UNWIND: ', CHPL_UNWIND);
 writeln('CHPL_MEM: ', CHPL_MEM);
 writeln('CHPL_MAKE: ', CHPL_MAKE);
 writeln('CHPL_ATOMICS: ', CHPL_ATOMICS);

test/runtime/panzone/fact-stacktrace.chpl

@@ -0,0 +1,6 @@
+proc fact(i : int) :int{
+  if(i == 0) then halt();
+  else return i*fact(i-1);
+}
+
+fact(2);

test/runtime/panzone/fact-stacktrace.cleanfiles

@@ -0,0 +1 @@
+fact-stacktrace.good

test/runtime/panzone/fact-stacktrace.prediff

@@ -0,0 +1,11 @@
+#! /bin/bash
+
+echo "$1.chpl:2: error: halt reached" > $1.good
+echo "" >> $1.good
+echo "Stacktrace" >> $1.good
+echo "" >> $1.good
+echo "halt ($CHPL_HOME/modules/internal/ChapelIO.chpl:679)" >> $1.good
+echo "fact ($1.chpl:1)" >> $1.good
+echo "fact ($1.chpl:1)" >> $1.good
+echo "fact ($1.chpl:1)" >> $1.good
+echo "" >> $1.good

test/runtime/panzone/fact-stacktrace.skipif

@@ -0,0 +1,2 @@
+CHPL_RT_UNWIND==0
+CHPL_UNWIND==none

test/runtime/panzone/stacktrace.chpl

@@ -0,0 +1,13 @@
+proc a() {
+  halt();
+}
+
+proc b(){
+  a();
+}
+
+proc c(){
+  b();
+}
+
+c();

test/runtime/panzone/stacktrace.cleanfiles

@@ -0,0 +1 @@
+stacktrace.good

test/runtime/panzone/stacktrace.prediff

@@ -0,0 +1,11 @@
+#! /bin/bash
+
+echo "$1.chpl:2: error: halt reached" > $1.good
+echo "" >> $1.good
+echo "Stacktrace" >> $1.good
+echo "" >> $1.good
+echo "halt ($CHPL_HOME/modules/internal/ChapelIO.chpl:679)" >> $1.good
+echo "a ($1.chpl:1)" >> $1.good
+echo "b ($1.chpl:5)" >> $1.good
+echo "c ($1.chpl:9)" >> $1.good
+echo "" >> $1.good

test/runtime/panzone/stacktrace.skipif

@@ -0,0 +1,2 @@
+CHPL_RT_UNWIND==0
+CHPL_UNWIND==none