Bug 1504074 - Apply LLVM patch to close file mapping handles after __gcov_flush. r=dmajor

--HG--
extra : rebase_source : 46977cfb1a4b390083fcb0c57bec4e302013572f

build/build-clang/clang-win64.json

@@ -20,6 +20,7 @@
       "r343123-pin-asan-dll.patch",
       "aarch64-vastart-checking.patch",
       "downgrade-mangling-error.patch",
+      "r346300-compiler-rt-windows-mmap.patch",
       "loosen-msvc-detection.patch"
     ]
 }

build/build-clang/r346300-compiler-rt-windows-mmap.patch

@@ -0,0 +1,149 @@
+From 0b881f23c6f2a637ab97d71e964cc3743fef98b8 Mon Sep 17 00:00:00 2001
+From: Marco Castelluccio <mcastelluccio@mozilla.com>
+Date: Wed, 7 Nov 2018 09:38:26 +0000
+Subject: [PATCH] [GCOV] Close file mapping handle on Windows, so flushed gcda
+ files can be removed while the process is in execution
+
+git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@346300 91177308-0d34-0410-b5e6-96231b3b80d8
+---
+ lib/profile/GCDAProfiling.c                   | 49 +++++++++++++++++++
+ lib/profile/WindowsMMap.c                     |  8 ---
+ lib/profile/WindowsMMap.h                     |  8 +++
+ .../instrprof-gcov-__gcov_flush-multiple.c    | 16 ++++++
+ ...nstrprof-gcov-__gcov_flush-multiple.c.gcov | 21 ++++++++
+ .../instrprof-gcov-__gcov_flush-multiple.test | 10 ++++
+ 6 files changed, 104 insertions(+), 8 deletions(-)
+ create mode 100644 test/profile/Inputs/instrprof-gcov-__gcov_flush-multiple.c
+ create mode 100644 test/profile/Inputs/instrprof-gcov-__gcov_flush-multiple.c.gcov
+ create mode 100644 test/profile/instrprof-gcov-__gcov_flush-multiple.test
+
+diff --git a/compiler-rt/lib/profile/GCDAProfiling.c b/compiler-rt/lib/profile/GCDAProfiling.c
+index cbca36551..0665a680c 100644
+--- a/compiler-rt/lib/profile/GCDAProfiling.c
++++ b/compiler-rt/lib/profile/GCDAProfiling.c
+@@ -29,6 +29,8 @@
+ #include <string.h>
+ 
+ #if defined(_WIN32)
++#define WIN32_LEAN_AND_MEAN
++#include <windows.h>
+ #include "WindowsMMap.h"
+ #else
+ #include <sys/mman.h>
+@@ -86,6 +88,9 @@ static uint64_t cur_buffer_size = 0;
+ static uint64_t cur_pos = 0;
+ static uint64_t file_size = 0;
+ static int new_file = 0;
++#if defined(_WIN32)
++static HANDLE mmap_handle = NULL;
++#endif
+ static int fd = -1;
+ 
+ typedef void (*fn_ptr)();
+@@ -255,6 +260,28 @@ static int map_file() {
+   if (file_size == 0)
+     return -1;
+ 
++#if defined(_WIN32)
++  HANDLE mmap_fd;
++  if (fd == -1)
++    mmap_fd = INVALID_HANDLE_VALUE;
++  else
++    mmap_fd = (HANDLE)_get_osfhandle(fd);
++
++  mmap_handle = CreateFileMapping(mmap_fd, NULL, PAGE_READWRITE, DWORD_HI(file_size), DWORD_LO(file_size), NULL);
++  if (mmap_handle == NULL) {
++    fprintf(stderr, "profiling: %s: cannot create file mapping: %d\n", filename,
++            GetLastError());
++    return -1;
++  }
++
++  write_buffer = MapViewOfFile(mmap_handle, FILE_MAP_WRITE, 0, 0, file_size);
++  if (write_buffer == NULL) {
++    fprintf(stderr, "profiling: %s: cannot map: %d\n", filename,
++            GetLastError());
++    CloseHandle(mmap_handle);
++    return -1;
++  }
++#else
+   write_buffer = mmap(0, file_size, PROT_READ | PROT_WRITE,
+                       MAP_FILE | MAP_SHARED, fd, 0);
+   if (write_buffer == (void *)-1) {
+@@ -263,10 +290,30 @@ static int map_file() {
+             strerror(errnum));
+     return -1;
+   }
++#endif
++
+   return 0;
+ }
+ 
+ static void unmap_file() {
++#if defined(_WIN32)
++  if (!FlushViewOfFile(write_buffer, file_size)) {
++    fprintf(stderr, "profiling: %s: cannot flush mapped view: %d\n", filename,
++            GetLastError());
++  }
++
++  if (!UnmapViewOfFile(write_buffer)) {
++    fprintf(stderr, "profiling: %s: cannot unmap mapped view: %d\n", filename,
++            GetLastError());
++  }
++
++  if (!CloseHandle(mmap_handle)) {
++    fprintf(stderr, "profiling: %s: cannot close file mapping handle: %d\n", filename,
++            GetLastError());
++  }
++
++  mmap_handle = NULL;
++#else
+   if (msync(write_buffer, file_size, MS_SYNC) == -1) {
+     int errnum = errno;
+     fprintf(stderr, "profiling: %s: cannot msync: %s\n", filename,
+@@ -277,6 +324,8 @@ static void unmap_file() {
+    * is written and we don't care.
+    */
+   (void)munmap(write_buffer, file_size);
++#endif
++
+   write_buffer = NULL;
+   file_size = 0;
+ }
+diff --git a/compiler-rt/lib/profile/WindowsMMap.c b/compiler-rt/lib/profile/WindowsMMap.c
+index dc87a888a..41cc67f41 100644
+--- a/compiler-rt/lib/profile/WindowsMMap.c
++++ b/compiler-rt/lib/profile/WindowsMMap.c
+@@ -24,14 +24,6 @@
+ 
+ #include "InstrProfiling.h"
+ 
+-#ifdef __USE_FILE_OFFSET64
+-# define DWORD_HI(x) (x >> 32)
+-# define DWORD_LO(x) ((x) & 0xffffffff)
+-#else
+-# define DWORD_HI(x) (0)
+-# define DWORD_LO(x) (x)
+-#endif
+-
+ COMPILER_RT_VISIBILITY
+ void *mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
+ {
+diff --git a/compiler-rt/lib/profile/WindowsMMap.h b/compiler-rt/lib/profile/WindowsMMap.h
+index ac2c911c8..51a130b31 100644
+--- a/compiler-rt/lib/profile/WindowsMMap.h
++++ b/compiler-rt/lib/profile/WindowsMMap.h
+@@ -45,6 +45,14 @@
+ #define   LOCK_NB   4    /* don't block when locking */
+ #define   LOCK_UN   8    /* unlock */
+ 
++#ifdef __USE_FILE_OFFSET64
++# define DWORD_HI(x) (x >> 32)
++# define DWORD_LO(x) ((x) & 0xffffffff)
++#else
++# define DWORD_HI(x) (0)
++# define DWORD_LO(x) (x)
++#endif
++
+ void *mmap(void *start, size_t length, int prot, int flags, int fd,
+            off_t offset);
+