Merge remote-tracking branch 'origin/4.0'

Change-Id: If61899521e38e744742711b84acbeb31aadd92f2

7 files changed, 130 insertions, 42 deletions

diff --git a/3rdparty/elfutils/backends/aarch64/aarch64.pro b/3rdparty/elfutils/backends/aarch64/aarch64.pro
index 5489b1d..a53be98 100644
--- a/3rdparty/elfutils/backends/aarch64/aarch64.pro
+++ b/3rdparty/elfutils/backends/aarch64/aarch64.pro
@@ -8,7 +8,8 @@ SOURCES += \
     ../aarch64_initreg.c \
     ../aarch64_regs.c \
     ../aarch64_retval.c \
-    ../aarch64_symbol.c
+    ../aarch64_symbol.c \
+    ../aarch64_unwind.c
 
 HEADERS += \
     ../aarch64_reloc.def
diff --git a/3rdparty/elfutils/backends/aarch64_init.c b/3rdparty/elfutils/backends/aarch64_init.c
index b0fd17a..8a96f73 100644
--- a/3rdparty/elfutils/backends/aarch64_init.c
+++ b/3rdparty/elfutils/backends/aarch64_init.c
@@ -64,6 +64,7 @@ aarch64_init (elf, machine, eh, ehlen)
      + ALT_FRAME_RETURN_COLUMN (used when LR isn't used) = 97 DWARF regs. */
   eh->frame_nregs = 97;
   HOOK (eh, set_initial_registers_tid);
+  HOOK (eh, unwind);
 
   return MODVERSION;
 }
diff --git a/3rdparty/elfutils/backends/aarch64_unwind.c b/3rdparty/elfutils/backends/aarch64_unwind.c
new file mode 100644
index 0000000..5560c58
--- /dev/null
+++ b/3rdparty/elfutils/backends/aarch64_unwind.c
@@ -0,0 +1,78 @@
+/* Get previous frame state for an existing frame state.
+   Copyright (C) 2016 The Qt Company Ltd.
+   This file is part of elfutils.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at
+       your option) any later version
+
+   or both in parallel, as here.
+
+   elfutils is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <assert.h>
+
+#define BACKEND aarch64_
+#include "libebl_CPU.h"
+#include <stdio.h>
+
+/* There was no CFI. Maybe we happen to have a frame pointer and can unwind from that?  */
+
+bool
+aarch64_unwind (Ebl *ebl __attribute__ ((unused)), Dwarf_Addr pc __attribute__ ((unused)),
+         ebl_tid_registers_t *setfunc, ebl_tid_registers_get_t *getfunc,
+         ebl_pid_memory_read_t *readfunc, void *arg, bool *signal_framep)
+{
+  const int fpReg = 29;
+  const int lrReg = 30;
+  const int spReg = 31;
+
+  Dwarf_Word fp;
+  if (!getfunc(fpReg, 1, &fp, arg) || fp == 0)
+      return false;
+
+  Dwarf_Word lr;
+  if (!getfunc(lrReg, 1, &lr, arg))
+      return false;
+
+  Dwarf_Word newFp, newLr;
+  if (!readfunc(fp, &newFp, arg))
+      return false;
+  fp += 8;
+  if (!readfunc(fp, &newLr, arg))
+      return false;
+
+  fp += 8;
+  if (!setfunc(spReg, 1, &fp, arg))
+      return false;
+  if (!setfunc(fpReg, 1, &newFp, arg))
+      return false;
+  if (!setfunc(-1, 1, &newLr, arg))
+      return false;
+  if (!setfunc(lrReg, 1, &newLr, arg))
+      return false;
+
+  *signal_framep = false;
+  return true;
+}
diff --git a/3rdparty/elfutils/backends/arm_unwind.c b/3rdparty/elfutils/backends/arm_unwind.c
index 4d90db9..ea725cd 100644
--- a/3rdparty/elfutils/backends/arm_unwind.c
+++ b/3rdparty/elfutils/backends/arm_unwind.c
@@ -50,18 +50,18 @@ arm_unwind (Ebl *ebl __attribute__ ((unused)), Dwarf_Addr pc,
   const int lrReg = 14;
   const int spReg = 13;
 
-  Dwarf_Word fp = 0, lr = 0, sp = 0;
-  if (!getfunc(fpReg, 1, &fp, arg))
+  Dwarf_Word fp = 0, lr = 0, sp = 0; // have to be initialized because registers are 32bit only
+  if (!getfunc(fpReg, 1, &fp, arg) || fp == 0)
       return false;
   if (!getfunc(lrReg, 1, &lr, arg))
       return false;
   if (!getfunc(spReg, 1, &sp, arg))
       return false;
 
-  Dwarf_Word newFp = 0, newLr = 0;
+  Dwarf_Word newFp; // no initialization needed because we read 64bit
   if (!readfunc(fp, &newFp, arg))
       return false;
-  newLr = newFp >> 32;
+  Dwarf_Word newLr = newFp >> 32;
   newFp &= 0xffffffff;
 
   fp += 8;
diff --git a/3rdparty/elfutils/backends/x86_64_unwind.c b/3rdparty/elfutils/backends/x86_64_unwind.c
index 8b8b94a..2ad6102 100644
--- a/3rdparty/elfutils/backends/x86_64_unwind.c
+++ b/3rdparty/elfutils/backends/x86_64_unwind.c
@@ -48,7 +48,7 @@ x86_64_unwind (Ebl *ebl __attribute__ ((unused)), Dwarf_Addr pc __attribute__ ((
   const int spReg = 7;
 
   Dwarf_Word fp;
-  if (!getfunc(fpReg, 1, &fp, arg))
+  if (!getfunc(fpReg, 1, &fp, arg) || fp == 0)
     return false;
 
   Dwarf_Word prev_fp;
diff --git a/app/perfunwind.cpp b/app/perfunwind.cpp
index ae13b92..4170a8d 100644
--- a/app/perfunwind.cpp
+++ b/app/perfunwind.cpp
@@ -318,38 +318,46 @@ static const Dwfl_Thread_Callbacks callbacks = {
     nextThread, NULL, memoryRead, setInitialRegisters, NULL, NULL
 };
 
-static PerfUnwind::Frame lookupSymbol(PerfUnwind::UnwindInfo *ui, Dwfl *dwfl, Dwarf_Addr ip,
-                                      bool isKernel)
+PerfUnwind::Frame PerfUnwind::lookupSymbol(Dwarf_Addr ip, bool isKernel)
 {
+    quint32 pid = currentUnwind.sample->pid();
     Dwfl_Module *mod = dwfl ? dwfl_addrmodule(dwfl, ip) : 0;
-    QByteArray symname;
     QByteArray elfFile;
-    QByteArray srcFile;
-    int line = 0;
-    int column = 0;
-    GElf_Sym sym;
-    GElf_Off off = 0;
 
     if (dwfl && !mod) {
-        const PerfUnwind::ElfInfo *elfInfo = 0;
-        mod = ui->unwind->reportElf(ip, isKernel ? PerfUnwind::s_kernelPid : ui->sample->pid(),
-                                    &elfInfo);
+        const ElfInfo *elfInfo = 0;
+        mod = reportElf(ip, isKernel ? s_kernelPid : pid, &elfInfo);
         if (!mod && elfInfo)
             elfFile = elfInfo->file.fileName().toLocal8Bit();
     }
 
-    Dwarf_Addr adjusted = (ui->unwind->architecture() != PerfRegisterInfo::ARCH_ARM || (ip & 1)) ?
-                ip : ip + 1;
+    Dwarf_Addr adjusted = (architecture() != PerfRegisterInfo::ARCH_ARM || (ip & 1)) ? ip : ip + 1;
+    if (mod)
+        elfFile = dwfl_module_info(mod, 0, 0, 0, 0, 0, 0, 0);
+
+    QHash<Dwarf_Addr, Frame> &processAddrCache = addrCache[pid];
+    auto it = processAddrCache.constFind(ip);
+    // Check for elfFile as it might have loaded a different file to the same address in the mean
+    // time. We don't consider the case of loading the same file again at a different, overlapping
+    // offset.
+    if (it != processAddrCache.constEnd() && it->elfFile == elfFile)
+        return *it;
+
+    QByteArray symname;
+    QByteArray srcFile;
+    int line = 0;
+    int column = 0;
+    GElf_Sym sym;
+    GElf_Off off = 0;
+
     if (mod) {
         // For addrinfo we need the raw pointer into symtab, so we need to adjust ourselves.
         symname = dwfl_module_addrinfo(mod, adjusted, &off, &sym, 0, 0, 0);
         if (off == adjusted) // no symbol found
             off = 0;
-        else if (ui->unwind->granularity() == PerfUnwind::Function)
+        else if (granularity() == Function)
             adjusted -= off;
 
-        elfFile = dwfl_module_info(mod, 0, 0, 0, 0, 0, 0, 0);
-
         Dwfl_Line *srcLine = dwfl_module_getsrc(mod, adjusted);
         if (srcLine)
             srcFile = dwfl_lineinfo(srcLine, NULL, &line, &column, NULL, NULL);
@@ -360,20 +368,23 @@ static PerfUnwind::Frame lookupSymbol(PerfUnwind::UnwindInfo *ui, Dwfl *dwfl, Dw
         int status = -1;
         if (symname[0] == '_' && symname[1] == 'Z')
             demangled = abi::__cxa_demangle(symname, 0, 0, &status);
-        else if (ui->unwind->architecture() == PerfRegisterInfo::ARCH_ARM && symname[0] == '$'
+        else if (architecture() == PerfRegisterInfo::ARCH_ARM && symname[0] == '$'
                  && (symname[1] == 'a' || symname[1] == 't') && symname[2] == '\0')
-            ui->isInterworking = true;
+            currentUnwind.isInterworking = true;
 
         // Adjust it back. The symtab entries are 1 off for all practical purposes.
-        PerfUnwind::Frame frame(adjusted, isKernel, status == 0 ? QByteArray(demangled) : symname,
-                                elfFile, srcFile, line, column);
+        Frame frame(adjusted, isKernel, status == 0 ? QByteArray(demangled) : symname, elfFile,
+                    srcFile, line, column);
         free(demangled);
+        processAddrCache.insert(ip, frame);
         return frame;
     } else {
-        symname = ui->unwind->symbolFromPerfMap(adjusted, ui->sample->pid(), &off);
-        if (ui->unwind->granularity() == PerfUnwind::Function)
+        symname = symbolFromPerfMap(adjusted, pid, &off);
+        if (granularity() == Function)
             adjusted -= off;
-        return PerfUnwind::Frame(adjusted, isKernel, symname, elfFile, srcFile, line, column);
+        Frame frame(adjusted, isKernel, symname, elfFile, srcFile, line, column);
+        processAddrCache.insert(ip, frame);
+        return frame;
     }
 }
 
@@ -392,12 +403,8 @@ static int frameCallback(Dwfl_Frame *state, void *arg)
 
     Dwarf_Addr pc_adjusted = pc - (isactivation ? 0 : 1);
 
-    /* Get PC->SYMNAME.  */
-    Dwfl_Thread *thread = dwfl_frame_thread (state);
-    Dwfl *dwfl = dwfl_thread_dwfl (thread);
-
     // isKernel = false as unwinding generally only works on user code
-    ui->frames.append(lookupSymbol(ui, dwfl, pc_adjusted, false));
+    ui->frames.append(ui->unwind->lookupSymbol(pc_adjusted, false));
     return DWARF_CB_OK;
 }
 
@@ -438,11 +445,10 @@ void PerfUnwind::resolveCallchain()
 
         // sometimes it skips the first user frame.
         if (i == 0 && !isKernel && ip != currentUnwind.sample->ip())
-            currentUnwind.frames.append(lookupSymbol(&currentUnwind, dwfl,
-                                                     currentUnwind.sample->ip(), false));
+            currentUnwind.frames.append(lookupSymbol(currentUnwind.sample->ip(), false));
 
         if (ip <= PERF_CONTEXT_MAX)
-            currentUnwind.frames.append(lookupSymbol(&currentUnwind, dwfl, ip, isKernel));
+            currentUnwind.frames.append(lookupSymbol(ip, isKernel));
     }
 }
 
@@ -491,10 +497,8 @@ void PerfUnwind::analyze(const PerfRecordSample &sample)
             unwindStack();
     }
     // If nothing was found, at least look up the IP
-    if (currentUnwind.frames.isEmpty()) {
-        currentUnwind.frames.append(lookupSymbol(&currentUnwind, dwfl, sample.ip(),
-                                                 ipIsInKernelSpace(sample.ip())));
-    }
+    if (currentUnwind.frames.isEmpty())
+        currentUnwind.frames.append(lookupSymbol(sample.ip(), ipIsInKernelSpace(sample.ip())));
 
     QByteArray buffer;
     QDataStream(&buffer, QIODevice::WriteOnly)
diff --git a/app/perfunwind.h b/app/perfunwind.h
index f7a3520..2b07131 100644
--- a/app/perfunwind.h
+++ b/app/perfunwind.h
@@ -64,7 +64,7 @@ public:
     struct UnwindInfo {
         UnwindInfo() : frames(0), unwind(0), sample(0), broken(false), isInterworking(false) {}
         QVector<PerfUnwind::Frame> frames;
-        const PerfUnwind *unwind;
+        PerfUnwind *unwind;
         const PerfRecordSample *sample;
         bool broken;
         bool isInterworking;
@@ -120,6 +120,8 @@ public:
     QByteArray symbolFromPerfMap(quint64 ip, quint32 pid, GElf_Off *offset) const;
     void updatePerfMap(quint32 pid);
 
+    Frame lookupSymbol(Dwarf_Addr ip, bool isKernel);
+
 private:
 
     enum CallchainContext {
@@ -159,6 +161,8 @@ private:
     QHash<quint32, QMap<quint64, ElfInfo> > elfs; // The inner map needs to be sorted
     QHash<quint32, PerfMap> perfMaps;
     QList<PerfRecordSample> sampleBuffer;
+    QHash<quint32, QHash<Dwarf_Addr, Frame> > addrCache;
+
     uint sampleBufferSize;
 
     Granularity sampleGranularity;