[compiler-rt] r307695 - Inline function to get mac segment address range
Francis Ricci via llvm-commits
llvm-commits at lists.llvm.org
Tue Jul 11 12:40:53 PDT 2017
Author: fjricci
Date: Tue Jul 11 12:40:53 2017
New Revision: 307695
URL: http://llvm.org/viewvc/llvm-project?rev=307695&view=rev
Log:
Inline function to get mac segment address range
Summary:
This function is only called once and is fairly simple. Inline to
keep API simple.
Reviewers: alekseyshl, kubamracek
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D35270
Modified:
compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps.h
compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps_mac.cc
Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps.h?rev=307695&r1=307694&r2=307695&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps.h (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps.h Tue Jul 11 12:40:53 2017
@@ -86,8 +86,6 @@ class MemoryMappingLayout {
# elif SANITIZER_MAC
template <u32 kLCSegment, typename SegmentCommand>
bool NextSegmentLoad(MemoryMappedSegment *segment);
- void GetSegmentAddrRange(MemoryMappedSegment *segment, uptr vmaddr,
- uptr vmsize);
int current_image_;
u32 current_magic_;
u32 current_filetype_;
Modified: compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps_mac.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps_mac.cc?rev=307695&r1=307694&r2=307695&view=diff
==============================================================================
--- compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps_mac.cc (original)
+++ compiler-rt/trunk/lib/sanitizer_common/sanitizer_procmaps_mac.cc Tue Jul 11 12:40:53 2017
@@ -88,6 +88,48 @@ void MemoryMappingLayout::LoadFromCache(
// No-op on Mac for now.
}
+// _dyld_get_image_header() and related APIs don't report dyld itself.
+// We work around this by manually recursing through the memory map
+// until we hit a Mach header matching dyld instead. These recurse
+// calls are expensive, but the first memory map generation occurs
+// early in the process, when dyld is one of the only images loaded,
+// so it will be hit after only a few iterations.
+static mach_header *get_dyld_image_header() {
+ mach_port_name_t port;
+ if (task_for_pid(mach_task_self(), internal_getpid(), &port) !=
+ KERN_SUCCESS) {
+ return nullptr;
+ }
+
+ unsigned depth = 1;
+ vm_size_t size = 0;
+ vm_address_t address = 0;
+ kern_return_t err = KERN_SUCCESS;
+ mach_msg_type_number_t count = VM_REGION_SUBMAP_INFO_COUNT_64;
+
+ while (true) {
+ struct vm_region_submap_info_64 info;
+ err = vm_region_recurse_64(port, &address, &size, &depth,
+ (vm_region_info_t)&info, &count);
+ if (err != KERN_SUCCESS) return nullptr;
+
+ if (size >= sizeof(mach_header) && info.protection & kProtectionRead) {
+ mach_header *hdr = (mach_header *)address;
+ if ((hdr->magic == MH_MAGIC || hdr->magic == MH_MAGIC_64) &&
+ hdr->filetype == MH_DYLINKER) {
+ return hdr;
+ }
+ }
+ address += size;
+ }
+}
+
+const mach_header *get_dyld_hdr() {
+ if (!dyld_hdr) dyld_hdr = get_dyld_image_header();
+
+ return dyld_hdr;
+}
+
// Next and NextSegmentLoad were inspired by base/sysinfo.cc in
// Google Perftools, https://github.com/gperftools/gperftools.
@@ -101,7 +143,22 @@ bool MemoryMappingLayout::NextSegmentLoa
current_load_cmd_addr_ += ((const load_command *)lc)->cmdsize;
if (((const load_command *)lc)->cmd == kLCSegment) {
const SegmentCommand* sc = (const SegmentCommand *)lc;
- GetSegmentAddrRange(segment, sc->vmaddr, sc->vmsize);
+
+ if (current_image_ == kDyldImageIdx) {
+ // vmaddr is masked with 0xfffff because on macOS versions < 10.12,
+ // it contains an absolute address rather than an offset for dyld.
+ // To make matters even more complicated, this absolute address
+ // isn't actually the absolute segment address, but the offset portion
+ // of the address is accurate when combined with the dyld base address,
+ // and the mask will give just this offset.
+ segment->start = (sc->vmaddr & 0xfffff) + (uptr)get_dyld_hdr();
+ segment->end = (sc->vmaddr & 0xfffff) + sc->vmsize + (uptr)get_dyld_hdr();
+ } else {
+ const sptr dlloff = _dyld_get_image_vmaddr_slide(current_image_);
+ segment->start = sc->vmaddr + dlloff;
+ segment->end = sc->vmaddr + sc->vmsize + dlloff;
+ }
+
// Return the initial protection.
segment->protection = sc->initprot;
segment->offset =
@@ -174,66 +231,6 @@ static bool IsModuleInstrumented(const l
return false;
}
-// _dyld_get_image_header() and related APIs don't report dyld itself.
-// We work around this by manually recursing through the memory map
-// until we hit a Mach header matching dyld instead. These recurse
-// calls are expensive, but the first memory map generation occurs
-// early in the process, when dyld is one of the only images loaded,
-// so it will be hit after only a few iterations.
-static mach_header *get_dyld_image_header() {
- mach_port_name_t port;
- if (task_for_pid(mach_task_self(), internal_getpid(), &port) !=
- KERN_SUCCESS) {
- return nullptr;
- }
-
- unsigned depth = 1;
- vm_size_t size = 0;
- vm_address_t address = 0;
- kern_return_t err = KERN_SUCCESS;
- mach_msg_type_number_t count = VM_REGION_SUBMAP_INFO_COUNT_64;
-
- while (true) {
- struct vm_region_submap_info_64 info;
- err = vm_region_recurse_64(port, &address, &size, &depth,
- (vm_region_info_t)&info, &count);
- if (err != KERN_SUCCESS) return nullptr;
-
- if (size >= sizeof(mach_header) && info.protection & kProtectionRead) {
- mach_header *hdr = (mach_header *)address;
- if ((hdr->magic == MH_MAGIC || hdr->magic == MH_MAGIC_64) &&
- hdr->filetype == MH_DYLINKER) {
- return hdr;
- }
- }
- address += size;
- }
-}
-
-const mach_header *get_dyld_hdr() {
- if (!dyld_hdr) dyld_hdr = get_dyld_image_header();
-
- return dyld_hdr;
-}
-
-void MemoryMappingLayout::GetSegmentAddrRange(MemoryMappedSegment *segment,
- uptr vmaddr, uptr vmsize) {
- if (current_image_ == kDyldImageIdx) {
- // vmaddr is masked with 0xfffff because on macOS versions < 10.12,
- // it contains an absolute address rather than an offset for dyld.
- // To make matters even more complicated, this absolute address
- // isn't actually the absolute segment address, but the offset portion
- // of the address is accurate when combined with the dyld base address,
- // and the mask will give just this offset.
- segment->start = (vmaddr & 0xfffff) + (uptr)get_dyld_hdr();
- segment->end = (vmaddr & 0xfffff) + vmsize + (uptr)get_dyld_hdr();
- } else {
- const sptr dlloff = _dyld_get_image_vmaddr_slide(current_image_);
- segment->start = vmaddr + dlloff;
- segment->end = vmaddr + vmsize + dlloff;
- }
-}
-
bool MemoryMappingLayout::Next(MemoryMappedSegment *segment) {
for (; current_image_ >= kDyldImageIdx; current_image_--) {
const mach_header *hdr = (current_image_ == kDyldImageIdx)
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