#include <windows.h>
#endif
-#if defined(openbsd_HOST_OS)
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/mman.h>
-
-/* no C99 header stdint.h on OpenBSD? */
-typedef unsigned long my_uintptr_t;
-#endif
-
#if defined(powerpc_HOST_ARCH) && defined(linux_HOST_OS)
#include <string.h>
#endif
-/* Heavily arch-specific, I'm afraid.. */
+#ifdef LEADING_UNDERSCORE
+#define UNDERSCORE "_"
+#else
+#define UNDERSCORE ""
+#endif
+#if defined(i386_HOST_ARCH) && !defined(darwin_HOST_OS)
+/*
+ Now here's something obscure for you:
-/*
- * Allocate len bytes which are readable, writable, and executable.
- *
- * ToDo: If this turns out to be a performance bottleneck, one could
- * e.g. cache the last VirtualProtect/mprotect-ed region and do
- * nothing in case of a cache hit.
- */
-static void*
-mallocBytesRWX(int len)
+ When generating an adjustor thunk that uses the C calling
+ convention, we have to make sure that the thunk kicks off
+ the process of jumping into Haskell with a tail jump. Why?
+ Because as a result of jumping in into Haskell we may end
+ up freeing the very adjustor thunk we came from using
+ freeHaskellFunctionPtr(). Hence, we better not return to
+ the adjustor code on our way out, since it could by then
+ point to junk.
+
+ The fix is readily at hand, just include the opcodes
+ for the C stack fixup code that we need to perform when
+ returning in some static piece of memory and arrange
+ to return to it before tail jumping from the adjustor thunk.
+*/
+static void GNUC3_ATTRIBUTE(used) obscure_ccall_wrapper(void)
{
- void *addr = stgMallocBytes(len, "mallocBytesRWX");
-#if defined(i386_HOST_ARCH) && defined(_WIN32)
- /* This could be necessary for processors which distinguish between READ and
- EXECUTE memory accesses, e.g. Itaniums. */
- DWORD dwOldProtect = 0;
- if (VirtualProtect (addr, len, PAGE_EXECUTE_READWRITE, &dwOldProtect) == 0) {
- barf("mallocBytesRWX: failed to protect 0x%p; error=%lu; old protection: %lu\n",
- addr, (unsigned long)GetLastError(), (unsigned long)dwOldProtect);
- }
-#elif defined(openbsd_HOST_OS)
- /* malloced memory isn't executable by default on OpenBSD */
- my_uintptr_t pageSize = sysconf(_SC_PAGESIZE);
- my_uintptr_t mask = ~(pageSize - 1);
- my_uintptr_t startOfFirstPage = ((my_uintptr_t)addr ) & mask;
- my_uintptr_t startOfLastPage = ((my_uintptr_t)addr + len - 1) & mask;
- my_uintptr_t size = startOfLastPage - startOfFirstPage + pageSize;
- if (mprotect((void*)startOfFirstPage, (size_t)size, PROT_EXEC | PROT_READ | PROT_WRITE) != 0) {
- barf("mallocBytesRWX: failed to protect 0x%p\n", addr);
- }
-#endif
- return addr;
+ __asm__ (
+ ".globl " UNDERSCORE "obscure_ccall_ret_code\n"
+ UNDERSCORE "obscure_ccall_ret_code:\n\t"
+ "addl $0x4, %esp\n\t"
+ "ret"
+ );
}
+extern void obscure_ccall_ret_code(void);
+
+#if defined(openbsd_HOST_OS)
+static unsigned char *obscure_ccall_ret_code_dyn;
+#endif
-#if defined(i386_HOST_ARCH)
-static unsigned char *obscure_ccall_ret_code;
+#endif
+
+#if defined(x86_64_HOST_ARCH)
+static void GNUC3_ATTRIBUTE(used) obscure_ccall_wrapper(void)
+{
+ __asm__ (
+ ".globl " UNDERSCORE "obscure_ccall_ret_code\n"
+ UNDERSCORE "obscure_ccall_ret_code:\n\t"
+ "addq $0x8, %rsp\n\t"
+ "ret"
+ );
+}
+extern void obscure_ccall_ret_code(void);
#endif
#if defined(alpha_HOST_ARCH)
*stable = getStablePtr((StgPtr)arr);
/* and return a ptr to the goods inside the array */
- return(BYTE_ARR_CTS(arr));
+ return(&(arr->payload));
}
#endif
#endif
#endif
+#if defined(i386_HOST_ARCH) && defined(darwin_HOST_OS)
+
+/* !!! !!! WARNING: !!! !!!
+ * This structure is accessed from AdjustorAsm.s
+ * Any changes here have to be mirrored in the offsets there.
+ */
+
+typedef struct AdjustorStub {
+ unsigned char call[8];
+ StgStablePtr hptr;
+ StgFunPtr wptr;
+ StgInt frame_size;
+ StgInt argument_size;
+} AdjustorStub;
+#endif
+
+#if defined(darwin_HOST_OS) || defined(powerpc_HOST_ARCH) || defined(powerpc64_HOST_ARCH)
+static int totalArgumentSize(char *typeString)
+{
+ int sz = 0;
+ while(*typeString)
+ {
+ char t = *typeString++;
+
+ switch(t)
+ {
+ // on 32-bit platforms, Double and Int64 occupy two words.
+ case 'd':
+ case 'l':
+ if(sizeof(void*) == 4)
+ {
+ sz += 2;
+ break;
+ }
+ // everything else is one word.
+ default:
+ sz += 1;
+ }
+ }
+ return sz;
+}
+#endif
+
void*
createAdjustor(int cconv, StgStablePtr hptr,
StgFunPtr wptr,
char *typeString
-#if !defined(powerpc_HOST_ARCH) && !defined(powerpc64_HOST_ARCH)
+#if !defined(powerpc_HOST_ARCH) && !defined(powerpc64_HOST_ARCH) && !defined(x86_64_HOST_ARCH)
STG_UNUSED
#endif
)
switch (cconv)
{
case 0: /* _stdcall */
-#if defined(i386_HOST_ARCH)
+#if defined(i386_HOST_ARCH) && !defined(darwin_HOST_OS)
/* Magic constant computed by inspecting the code length of
the following assembly language snippet
(offset and machine code prefixed):
<c>: ff e0 jmp %eax # and jump to it.
# the callee cleans up the stack
*/
- adjustor = mallocBytesRWX(14);
+ adjustor = stgMallocBytesRWX(14);
{
unsigned char *const adj_code = (unsigned char *)adjustor;
adj_code[0x00] = (unsigned char)0x58; /* popl %eax */
break;
case 1: /* _ccall */
-#if defined(i386_HOST_ARCH)
+#if defined(i386_HOST_ARCH) && !defined(darwin_HOST_OS)
/* Magic constant computed by inspecting the code length of
the following assembly language snippet
(offset and machine code prefixed):
That's (thankfully) the case here with the restricted set of
return types that we support.
*/
- adjustor = mallocBytesRWX(17);
+ adjustor = stgMallocBytesRWX(17);
{
unsigned char *const adj_code = (unsigned char *)adjustor;
*((StgFunPtr*)(adj_code + 0x06)) = (StgFunPtr)wptr;
adj_code[0x0a] = (unsigned char)0x68; /* pushl obscure_ccall_ret_code */
- *((StgFunPtr*)(adj_code + 0x0b)) = (StgFunPtr)obscure_ccall_ret_code;
+ *((StgFunPtr*)(adj_code + 0x0b)) =
+#if !defined(openbsd_HOST_OS)
+ (StgFunPtr)obscure_ccall_ret_code;
+#else
+ (StgFunPtr)obscure_ccall_ret_code_dyn;
+#endif
adj_code[0x0f] = (unsigned char)0xff; /* jmp *%eax */
adj_code[0x10] = (unsigned char)0xe0;
}
+#elif defined(i386_HOST_ARCH) && defined(darwin_HOST_OS)
+ {
+ /*
+ What's special about Darwin/Mac OS X on i386?
+ It wants the stack to stay 16-byte aligned.
+
+ We offload most of the work to AdjustorAsm.S.
+ */
+ AdjustorStub *adjustorStub = stgMallocBytesRWX(sizeof(AdjustorStub));
+ adjustor = adjustorStub;
+
+ extern void adjustorCode(void);
+ int sz = totalArgumentSize(typeString);
+
+ adjustorStub->call[0] = 0xe8;
+ *(long*)&adjustorStub->call[1] = ((char*)&adjustorCode) - ((char*)adjustorStub + 5);
+ adjustorStub->hptr = hptr;
+ adjustorStub->wptr = wptr;
+
+ // The adjustor puts the following things on the stack:
+ // 1.) %ebp link
+ // 2.) padding and (a copy of) the arguments
+ // 3.) a dummy argument
+ // 4.) hptr
+ // 5.) return address (for returning to the adjustor)
+ // All these have to add up to a multiple of 16.
+
+ // first, include everything in frame_size
+ adjustorStub->frame_size = sz * 4 + 16;
+ // align to 16 bytes
+ adjustorStub->frame_size = (adjustorStub->frame_size + 15) & ~15;
+ // only count 2.) and 3.) as part of frame_size
+ adjustorStub->frame_size -= 12;
+ adjustorStub->argument_size = sz;
+ }
+
+#elif defined(x86_64_HOST_ARCH)
+ /*
+ stack at call:
+ argn
+ ...
+ arg7
+ return address
+ %rdi,%rsi,%rdx,%rcx,%r8,%r9 = arg0..arg6
+
+ if there are <6 integer args, then we can just push the
+ StablePtr into %edi and shuffle the other args up.
+
+ If there are >=6 integer args, then we have to flush one arg
+ to the stack, and arrange to adjust the stack ptr on return.
+ The stack will be rearranged to this:
+
+ argn
+ ...
+ arg7
+ return address *** <-- dummy arg in stub fn.
+ arg6
+ obscure_ccall_ret_code
+
+ This unfortunately means that the type of the stub function
+ must have a dummy argument for the original return address
+ pointer inserted just after the 6th integer argument.
+
+ Code for the simple case:
+
+ 0: 4d 89 c1 mov %r8,%r9
+ 3: 49 89 c8 mov %rcx,%r8
+ 6: 48 89 d1 mov %rdx,%rcx
+ 9: 48 89 f2 mov %rsi,%rdx
+ c: 48 89 fe mov %rdi,%rsi
+ f: 48 8b 3d 0a 00 00 00 mov 10(%rip),%rdi
+ 16: ff 25 0c 00 00 00 jmpq *12(%rip)
+ ...
+ 20: .quad 0 # aligned on 8-byte boundary
+ 28: .quad 0 # aligned on 8-byte boundary
+
+
+ And the version for >=6 integer arguments:
+
+ 0: 41 51 push %r9
+ 2: ff 35 20 00 00 00 pushq 32(%rip) # 28 <ccall_adjustor+0x28>
+ 8: 4d 89 c1 mov %r8,%r9
+ b: 49 89 c8 mov %rcx,%r8
+ e: 48 89 d1 mov %rdx,%rcx
+ 11: 48 89 f2 mov %rsi,%rdx
+ 14: 48 89 fe mov %rdi,%rsi
+ 17: 48 8b 3d 12 00 00 00 mov 18(%rip),%rdi # 30 <ccall_adjustor+0x30>
+ 1e: ff 25 14 00 00 00 jmpq *20(%rip) # 38 <ccall_adjustor+0x38>
+ ...
+ 28: .quad 0 # aligned on 8-byte boundary
+ 30: .quad 0 # aligned on 8-byte boundary
+ 38: .quad 0 # aligned on 8-byte boundary
+ */
+
+ /* we assume the small code model (gcc -mcmmodel=small) where
+ * all symbols are <2^32, so hence wptr should fit into 32 bits.
+ */
+ ASSERT(((long)wptr >> 32) == 0);
+
+ {
+ int i = 0;
+ char *c;
+
+ // determine whether we have 6 or more integer arguments,
+ // and therefore need to flush one to the stack.
+ for (c = typeString; *c != '\0'; c++) {
+ if (*c == 'i' || *c == 'l') i++;
+ if (i == 6) break;
+ }
+
+ if (i < 6) {
+ adjustor = stgMallocBytesRWX(0x30);
+
+ *(StgInt32 *)adjustor = 0x49c1894d;
+ *(StgInt32 *)(adjustor+0x4) = 0x8948c889;
+ *(StgInt32 *)(adjustor+0x8) = 0xf28948d1;
+ *(StgInt32 *)(adjustor+0xc) = 0x48fe8948;
+ *(StgInt32 *)(adjustor+0x10) = 0x000a3d8b;
+ *(StgInt32 *)(adjustor+0x14) = 0x25ff0000;
+ *(StgInt32 *)(adjustor+0x18) = 0x0000000c;
+ *(StgInt64 *)(adjustor+0x20) = (StgInt64)hptr;
+ *(StgInt64 *)(adjustor+0x28) = (StgInt64)wptr;
+ }
+ else
+ {
+ adjustor = stgMallocBytesRWX(0x40);
+
+ *(StgInt32 *)adjustor = 0x35ff5141;
+ *(StgInt32 *)(adjustor+0x4) = 0x00000020;
+ *(StgInt32 *)(adjustor+0x8) = 0x49c1894d;
+ *(StgInt32 *)(adjustor+0xc) = 0x8948c889;
+ *(StgInt32 *)(adjustor+0x10) = 0xf28948d1;
+ *(StgInt32 *)(adjustor+0x14) = 0x48fe8948;
+ *(StgInt32 *)(adjustor+0x18) = 0x00123d8b;
+ *(StgInt32 *)(adjustor+0x1c) = 0x25ff0000;
+ *(StgInt32 *)(adjustor+0x20) = 0x00000014;
+
+ *(StgInt64 *)(adjustor+0x28) = (StgInt64)obscure_ccall_ret_code;
+ *(StgInt64 *)(adjustor+0x30) = (StgInt64)hptr;
+ *(StgInt64 *)(adjustor+0x38) = (StgInt64)wptr;
+ }
+ }
#elif defined(sparc_HOST_ARCH)
/* Magic constant computed by inspecting the code length of the following
assembly language snippet (offset and machine code prefixed):
similarly, and local variables should be accessed via %fp, not %sp. In a
nutshell: This should work! (Famous last words! :-)
*/
- adjustor = mallocBytesRWX(4*(11+1));
+ adjustor = stgMallocBytesRWX(4*(11+1));
{
unsigned long *const adj_code = (unsigned long *)adjustor;
4 bytes (getting rid of the nop), hence saving memory. [ccshan]
*/
ASSERT(((StgWord64)wptr & 3) == 0);
- adjustor = mallocBytesRWX(48);
+ adjustor = stgMallocBytesRWX(48);
{
StgWord64 *const code = (StgWord64 *)adjustor;
*/
// allocate space for at most 4 insns per parameter
// plus 14 more instructions.
- adjustor = mallocBytesRWX(4 * (4*n + 14));
+ adjustor = stgMallocBytesRWX(4 * (4*n + 14));
code = (unsigned*)adjustor;
*code++ = 0x48000008; // b *+8
#ifdef FUNDESCS
adjustorStub = stgMallocBytes(sizeof(AdjustorStub), "createAdjustor");
#else
- adjustorStub = mallocBytesRWX(sizeof(AdjustorStub));
+ adjustorStub = stgMallocBytesRWX(sizeof(AdjustorStub));
#endif
adjustor = adjustorStub;
#endif
// Calculate the size of the stack frame, in words.
- while(*typeString)
- {
- char t = *typeString++;
-
- switch(t)
- {
-#if defined(powerpc_HOST_ARCH)
- // on 32-bit platforms, Double and Int64 occupy two words.
- case 'd':
- case 'l':
- sz += 2;
- break;
-#endif
- // everything else is one word.
- default:
- sz += 1;
- }
- }
+ sz = totalArgumentSize(typeString);
+
// The first eight words of the parameter area
// are just "backing store" for the parameters passed in
// the GPRs. extra_sz is the number of words beyond those first
void
freeHaskellFunctionPtr(void* ptr)
{
-#if defined(i386_HOST_ARCH)
+#if defined(i386_HOST_ARCH) && !defined(darwin_HOST_OS)
if ( *(unsigned char*)ptr != 0x68 &&
*(unsigned char*)ptr != 0x58 ) {
errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr);
freeStablePtr(*((StgStablePtr*)((unsigned char*)ptr + 0x01)));
} else {
freeStablePtr(*((StgStablePtr*)((unsigned char*)ptr + 0x02)));
- }
+ }
+#elif defined(x86_TARGET_ARCH) && defined(darwin_HOST_OS)
+if ( *(unsigned char*)ptr != 0xe8 ) {
+ errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr);
+ return;
+ }
+ freeStablePtr(((AdjustorStub*)ptr)->hptr);
+#elif defined(x86_64_HOST_ARCH)
+ if ( *(StgWord16 *)ptr == 0x894d ) {
+ freeStablePtr(*(StgStablePtr*)(ptr+0x20));
+ } else if ( *(StgWord16 *)ptr == 0x5141 ) {
+ freeStablePtr(*(StgStablePtr*)(ptr+0x30));
+ } else {
+ errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr);
+ return;
+ }
#elif defined(sparc_HOST_ARCH)
if ( *(unsigned long*)ptr != 0x9C23A008UL ) {
errorBelch("freeHaskellFunctionPtr: not for me, guv! %p\n", ptr);
void
initAdjustor(void)
{
-#if defined(i386_HOST_ARCH)
- /* Now here's something obscure for you:
-
- When generating an adjustor thunk that uses the C calling
- convention, we have to make sure that the thunk kicks off
- the process of jumping into Haskell with a tail jump. Why?
- Because as a result of jumping in into Haskell we may end
- up freeing the very adjustor thunk we came from using
- freeHaskellFunctionPtr(). Hence, we better not return to
- the adjustor code on our way out, since it could by then
- point to junk.
-
- The fix is readily at hand, just include the opcodes
- for the C stack fixup code that we need to perform when
- returning in some static piece of memory and arrange
- to return to it before tail jumping from the adjustor thunk.
- */
-
- obscure_ccall_ret_code = mallocBytesRWX(4);
-
- obscure_ccall_ret_code[0x00] = (unsigned char)0x83; /* addl $0x4, %esp */
- obscure_ccall_ret_code[0x01] = (unsigned char)0xc4;
- obscure_ccall_ret_code[0x02] = (unsigned char)0x04;
-
- obscure_ccall_ret_code[0x03] = (unsigned char)0xc3; /* ret */
+#if defined(i386_HOST_ARCH) && defined(openbsd_HOST_OS)
+ obscure_ccall_ret_code_dyn = stgMallocBytesRWX(4);
+ obscure_ccall_ret_code_dyn[0] = ((unsigned char *)obscure_ccall_ret_code)[0];
+ obscure_ccall_ret_code_dyn[1] = ((unsigned char *)obscure_ccall_ret_code)[1];
+ obscure_ccall_ret_code_dyn[2] = ((unsigned char *)obscure_ccall_ret_code)[2];
+ obscure_ccall_ret_code_dyn[3] = ((unsigned char *)obscure_ccall_ret_code)[3];
#endif
}