Add ocInit_MachO
authorMoritz Angermann <moritz.angermann@gmail.com>
Tue, 21 Mar 2017 15:01:11 +0000 (11:01 -0400)
committerBen Gamari <ben@smart-cactus.org>
Mon, 27 Mar 2017 01:37:22 +0000 (21:37 -0400)
This adds ocInit_MachO function, used to populate the extended
ObjectCode structure, and the corresponding stgFree.

It also adds defines for iOS, such that MachO.o is also compiled for iOS
targets.

Depends on D3239

---

This is just one of the pieces for the rts linker
support for ios (aarch64-macho)

---

The following diagram and legend tries to explain the dependencies a
bit:
```
  .- D3240
  v
D3255 <- D3252 <- This <- D3239
  ^
  '- D3238
```

- In D3238 we started allowing preloading object code with mmap
  in iOS, where we can't have r+w+x.
- In D3239 we introduced a richer extension of the object code
  data type to make working with mach-o files easier.
- In D3240 we set the stage to allow loading archives (.a) on iOS
- In D3251 we added init and deinit functions to populate and
  depopulate the enriched object code data structure for mach-o
  files.
- In D3252 we refactored most of the MachO.c file to use the
  new types and data structure.
- in D3255 we finally introduce the aarch64-mach-o linker.

Reviewers: rwbarton, bgamari, austin, erikd, simonmar

Subscribers: thomie

Differential Revision: https://phabricator.haskell.org/D3251

rts/Linker.c
rts/linker/LoadArchive.c
rts/linker/MachO.c
rts/linker/MachO.h

index 87f1eeb..529af9a 100644 (file)
@@ -1186,6 +1186,10 @@ void freeObjectCode (ObjectCode *oc)
     }
 #endif
 
+#if defined(OBJECTFORMAT_MACHO)
+    ocDeinit_MachO(oc);
+#endif
+
     stgFree(oc->fileName);
     stgFree(oc->archiveMemberName);
 
@@ -1389,6 +1393,11 @@ preloadObjectFile (pathchar *path)
 
    oc = mkOc(path, image, fileSize, true, NULL, misalignment);
 
+#ifdef OBJFORMAT_MACHO
+   if (ocVerifyImage_MachO( oc ))
+       ocInit_MachO( oc );
+#endif
+
    return oc;
 }
 
index f9997cf..a33c00d 100644 (file)
@@ -538,6 +538,9 @@ static HsInt loadArchive_ (pathchar *path)
 
             oc = mkOc(path, image, memberSize, false, archiveMemberName
                      , misalignment);
+#ifdef OBJFORMAT_MACHO
+            ocInit_MachO( oc );
+#endif
 
             stgFree(archiveMemberName);
 
index 55b2bf1..13508fa 100644 (file)
@@ -1,6 +1,6 @@
 #include "Rts.h"
 
-#ifdef darwin_HOST_OS
+#if defined(darwin_HOST_OS) || defined(ios_HOST_OS)
 
 #include "RtsUtils.h"
 #include "GetEnv.h"
@@ -17,7 +17,7 @@
 #include <mach-o/nlist.h>
 #include <mach-o/reloc.h>
 
-#if defined(HAVE_SYS_MMAN_H)
+#if defined(HAVE_SYS_MMAN_H) && RTS_LINKER_USE_MMAP
 #  include <sys/mman.h>
 #endif
 
 #define nlist nlist_64
 #endif
 
+/*
+ * Initialize some common data in the object code so we don't have to
+ * continuously look up the addresses.
+ */
+void
+ocInit_MachO(ObjectCode * oc)
+{
+    oc->info = (ObjectCodeFormatInfo*)stgCallocBytes(
+                1, sizeof(ObjectCodeFormatInfo),
+                "ocInit_MachO(ObjectCodeFormatInfo)");
+    oc->info->header  = (MachOHeader *) oc->image;
+    oc->info->symCmd  = NULL;
+    oc->info->segCmd  = NULL;
+    oc->info->dsymCmd = NULL;
+
+    MachOLoadCommand *lc = (MachOLoadCommand*)(oc->image + sizeof(MachOHeader));
+    for(size_t i = 0; i < oc->info->header->ncmds; i++) {
+        if (lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64) {
+            oc->info->segCmd = (MachOSegmentCommand*) lc;
+        }
+        else if (lc->cmd == LC_SYMTAB) {
+            oc->info->symCmd = (MachOSymtabCommand*) lc;
+        }
+        else if (lc->cmd == LC_DYSYMTAB) {
+            oc->info->dsymCmd = (MachODsymtabCommand*) lc;
+        }
+        lc = (MachOLoadCommand *) ( ((char*)lc) + lc->cmdsize );
+    }
+    if (NULL == oc->info->segCmd) {
+        barf("ocGetNames_MachO: no segment load command");
+    }
+
+    oc->info->macho_sections = (MachOSection*) (oc->info->segCmd+1);
+    oc->n_sections = oc->info->segCmd->nsects;
+
+    oc->info->nlist = oc->info->symCmd == NULL
+              ? NULL
+              : (MachONList *)(oc->image + oc->info->symCmd->symoff);
+    oc->info->names = oc->image + oc->info->symCmd->stroff;
+
+    /* If we have symbols, allocate and fill the macho_symbols
+     * This will make relocation easier.
+     */
+    oc->info->n_macho_symbols = 0;
+    oc->info->macho_symbols = NULL;
+
+    if(NULL != oc->info->nlist) {
+        oc->info->n_macho_symbols = oc->info->symCmd->nsyms;
+        oc->info->macho_symbols = (MachOSymbol*)stgCallocBytes(
+                                    oc->info->symCmd->nsyms,
+                                    sizeof(MachOSymbol),
+                                    "ocInit_MachO(MachOSymbol)");
+        for(uint32_t i = 0; i < oc->info->symCmd->nsyms; i++) {
+            oc->info->macho_symbols[i].name  = oc->info->names
+                                             + oc->info->nlist[i].n_un.n_strx;
+            oc->info->macho_symbols[i].nlist = &oc->info->nlist[i];
+             /* we don't have an address for this symbol yet; this will be
+              * populated during ocGetNames_MachO. hence addr = NULL
+              */
+            oc->info->macho_symbols[i].addr  = NULL;
+        }
+    }
+}
+
+void
+ocDeinit_MachO(ObjectCode * oc) {
+    if(oc->info->n_macho_symbols > 0) {
+        stgFree(oc->info->macho_symbols);
+    }
+    stgFree(oc->info);
+}
 static int
 resolveImports(
     ObjectCode* oc,
@@ -55,6 +126,7 @@ resolveImports(
     unsigned long *indirectSyms,
     struct nlist *nlist);
 
+#if NEED_SYMBOL_EXTRAS
 #if defined(powerpc_HOST_ARCH)
 int
 ocAllocateSymbolExtras_MachO(ObjectCode* oc)
@@ -144,6 +216,7 @@ ocAllocateSymbolExtras_MachO(ObjectCode* oc)
 #else
 #error Unknown MachO architecture
 #endif /* HOST_ARCH */
+#endif /* NEED_SYMBOL_EXTRAS */
 
 int
 ocVerifyImage_MachO(ObjectCode * oc)
@@ -153,7 +226,7 @@ ocVerifyImage_MachO(ObjectCode * oc)
 
     IF_DEBUG(linker, debugBelch("ocVerifyImage_MachO: start\n"));
 
-#if x86_64_HOST_ARCH || powerpc64_HOST_ARCH
+#if x86_64_HOST_ARCH || powerpc64_HOST_ARCH || aarch64_HOST_ARCH
     if(header->magic != MH_MAGIC_64) {
         errorBelch("Could not load image %s: bad magic!\n"
                    "  Expected %08x (64bit), got %08x%s\n",
@@ -1241,4 +1314,4 @@ machoGetMisalignment( FILE * f )
     return misalignment ? (16 - misalignment) : 0;
 }
 
-#endif /* darwin_HOST_OS */
+#endif /* darwin_HOST_OS, ios_HOST_OS */
index 8c7fb1f..9362eb7 100644 (file)
@@ -5,6 +5,10 @@
 
 #include "BeginPrivate.h"
 
+#include "MachOTypes.h"
+
+void ocInit_MachO          ( ObjectCode* oc );
+void ocDeinit_MachO        ( ObjectCode* oc );
 int ocVerifyImage_MachO    ( ObjectCode* oc );
 int ocGetNames_MachO       ( ObjectCode* oc );
 int ocResolve_MachO        ( ObjectCode* oc );