X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Frts%2FAdjustor.c;h=0c45f8c7bf7a4382a50d775938b196d609b72be6;hb=7bb0f34f7e8e75d19a730891de6fe76ce96860d5;hp=59119bfd0796307fba0ea4f14069a4cf02639292;hpb=153b9cb9b11e05c4edb1b6bc0a7b972660e41f70;p=ghc-hetmet.git diff --git a/ghc/rts/Adjustor.c b/ghc/rts/Adjustor.c index 59119bf..0c45f8c 100644 --- a/ghc/rts/Adjustor.c +++ b/ghc/rts/Adjustor.c @@ -46,13 +46,18 @@ Haskell side. #include #endif -#if defined(openbsd_HOST_OS) +#if defined(openbsd_HOST_OS) || defined(linux_HOST_OS) #include #include #include /* no C99 header stdint.h on OpenBSD? */ +#if defined(openbsd_HOST_OS) typedef unsigned long my_uintptr_t; +#else +#include +typedef uintptr_t my_uintptr_t; +#endif #endif #if defined(powerpc_HOST_ARCH) && defined(linux_HOST_OS) @@ -80,7 +85,7 @@ mallocBytesRWX(int len) 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) +#elif defined(openbsd_HOST_OS) || defined(linux_HOST_OS) /* malloced memory isn't executable by default on OpenBSD */ my_uintptr_t pageSize = sysconf(_SC_PAGESIZE); my_uintptr_t mask = ~(pageSize - 1); @@ -94,8 +99,57 @@ mallocBytesRWX(int len) return addr; } +#ifdef LEADING_UNDERSCORE +#define UNDERSCORE "_" +#else +#define UNDERSCORE "" +#endif #if defined(i386_HOST_ARCH) -static unsigned char *obscure_ccall_ret_code; +/* + 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. +*/ +static void GNUC3_ATTRIBUTE(used) obscure_ccall_wrapper(void) +{ + __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 + +#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) @@ -134,7 +188,7 @@ stgAllocStable(size_t size_in_bytes, StgStablePtr *stable) *stable = getStablePtr((StgPtr)arr); /* and return a ptr to the goods inside the array */ - return(BYTE_ARR_CTS(arr)); + return(&(arr->payload)); } #endif @@ -195,7 +249,7 @@ 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 ) @@ -274,11 +328,121 @@ createAdjustor(int cconv, StgStablePtr hptr, *((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(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: e9 00 00 00 00 jmpq stub_function + ... + 20: .quad 0 # aligned on 8-byte boundary + + + And the version for >=6 integer arguments: + + 0: 41 51 push %r9 + 2: 68 00 00 00 00 pushq $obscure_ccall_ret_code + 7: 4d 89 c1 mov %r8,%r9 + a: 49 89 c8 mov %rcx,%r8 + d: 48 89 d1 mov %rdx,%rcx + 10: 48 89 f2 mov %rsi,%rdx + 13: 48 89 fe mov %rdi,%rsi + 16: 48 8b 3d 0b 00 00 00 mov 11(%rip),%rdi + 1d: e9 00 00 00 00 jmpq stub_function + ... + 28: .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 = mallocBytesRWX(40); + + *(StgInt32 *)adjustor = 0x49c1894d; + *(StgInt32 *)(adjustor+4) = 0x8948c889; + *(StgInt32 *)(adjustor+8) = 0xf28948d1; + *(StgInt32 *)(adjustor+12) = 0x48fe8948; + *(StgInt32 *)(adjustor+16) = 0x000a3d8b; + *(StgInt32 *)(adjustor+20) = 0x00e90000; + + *(StgInt32 *)(adjustor+23) = + (StgInt32)((StgInt64)wptr - (StgInt64)adjustor - 27); + *(StgInt64 *)(adjustor+32) = (StgInt64)hptr; + } + else + { + adjustor = mallocBytesRWX(48); + + *(StgInt32 *)adjustor = 0x00685141; + *(StgInt32 *)(adjustor+4) = 0x4d000000; + *(StgInt32 *)(adjustor+8) = 0x8949c189; + *(StgInt32 *)(adjustor+12) = 0xd18948c8; + *(StgInt32 *)(adjustor+16) = 0x48f28948; + *(StgInt32 *)(adjustor+20) = 0x8b48fe89; + *(StgInt32 *)(adjustor+24) = 0x00000b3d; + *(StgInt32 *)(adjustor+28) = 0x0000e900; + + *(StgInt32 *)(adjustor+3) = + (StgInt32)(StgInt64)obscure_ccall_ret_code; + *(StgInt32 *)(adjustor+30) = + (StgInt32)((StgInt64)wptr - (StgInt64)adjustor - 34); + *(StgInt64 *)(adjustor+40) = (StgInt64)hptr; + } + } #elif defined(sparc_HOST_ARCH) /* Magic constant computed by inspecting the code length of the following assembly language snippet (offset and machine code prefixed): @@ -848,7 +1012,16 @@ freeHaskellFunctionPtr(void* ptr) freeStablePtr(*((StgStablePtr*)((unsigned char*)ptr + 0x01))); } else { freeStablePtr(*((StgStablePtr*)((unsigned char*)ptr + 0x02))); - } + } +#elif defined(x86_64_HOST_ARCH) + if ( *(StgWord16 *)ptr == 0x894d ) { + freeStablePtr(*(StgStablePtr*)(ptr+32)); + } else if ( *(StgWord16 *)ptr == 0x5141 ) { + freeStablePtr(*(StgStablePtr*)(ptr+40)); + } 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); @@ -906,30 +1079,11 @@ freeHaskellFunctionPtr(void* 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 = mallocBytesRWX(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 }