[project @ 2004-04-05 10:53:52 by simonpj]
[ghc-hetmet.git] / ghc / rts / Adjustor.c
index 2ea1240..b488d43 100644 (file)
@@ -40,11 +40,51 @@ Haskell side.
 #include "Rts.h"
 #include "RtsUtils.h"
 #include "RtsFlags.h"
-
 #include <stdlib.h>
 
+#if defined(_WIN32)
+#include <windows.h>
+#endif
+
 /* Heavily arch-specific, I'm afraid.. */
 
+/*
+ * Function: execPage()
+ *
+ * Set the executable bit on page containing addr. CURRENTLY DISABLED.
+ *
+ * TODO: Can the code span more than one page? If yes, we need to make two
+ * pages executable!
+ */
+static rtsBool
+execPage (void* addr, int writable)
+{
+#if defined(i386_TARGET_ARCH) && defined(_WIN32) && 0
+    SYSTEM_INFO sInfo;
+    DWORD dwOldProtect = 0;
+
+    /* doesn't return a result, so presumably it can't fail... */
+    GetSystemInfo(&sInfo);
+    
+    if ( VirtualProtect ( (void*)((unsigned long)addr & (sInfo.dwPageSize - 1)),
+                         sInfo.dwPageSize,
+                         ( writable ? PAGE_EXECUTE_READWRITE : PAGE_EXECUTE_READ),
+                         &dwOldProtect) == 0 ) {
+# if 1
+       DWORD rc = GetLastError();
+       fprintf(stderr, "execPage: failed to protect 0x%p; error=%lu; old protection: %lu\n", addr, rc, dwOldProtect);
+# endif
+       return rtsFalse;
+    }
+    return rtsTrue;
+#else
+    (void)addr;   (void)writable;   /* keep gcc -Wall happy */
+    return rtsTrue;
+#endif
+}
+
+
+static unsigned char __obscure_ccall_ret_code [] = 
 #if defined(i386_TARGET_ARCH)
 /* Now here's something obscure for you:
 
@@ -65,15 +105,52 @@ Haskell side.
    For this to work we make the assumption that bytes in .data
    are considered executable.
 */
-static unsigned char __obscure_ccall_ret_code [] = 
   { 0x83, 0xc4, 0x04 /* addl $0x4, %esp */
   , 0xc3             /* ret */
   };
+#else
+/* No such mind-twisters on non-Intel platforms */
+  { };
 #endif
 
 #if defined(alpha_TARGET_ARCH)
 /* To get the definition of PAL_imb: */
-#include <machine/pal.h>
+# if defined(linux_TARGET_OS)
+#  include <asm/pal.h>
+# else
+#  include <machine/pal.h>
+# endif
+#endif
+
+#if defined(ia64_TARGET_ARCH)
+#include "Storage.h"
+
+/* Layout of a function descriptor */
+typedef struct _IA64FunDesc {
+    StgWord64 ip;
+    StgWord64 gp;
+} IA64FunDesc;
+
+static void *
+stgAllocStable(size_t size_in_bytes, StgStablePtr *stable)
+{
+  StgArrWords* arr;
+  nat data_size_in_words, total_size_in_words;
+  
+  /* round up to a whole number of words */
+  data_size_in_words  = (size_in_bytes + sizeof(W_) + 1) / sizeof(W_);
+  total_size_in_words = sizeofW(StgArrWords) + data_size_in_words;
+  
+  /* allocate and fill it in */
+  arr = (StgArrWords *)allocate(total_size_in_words);
+  SET_ARR_HDR(arr, &stg_ARR_WORDS_info, CCCS, data_size_in_words);
+  /* obtain a stable ptr */
+  *stable = getStablePtr((StgPtr)arr);
+
+  /* and return a ptr to the goods inside the array */
+  return(BYTE_ARR_CTS(arr));
+}
 #endif
 
 void*
@@ -111,6 +188,8 @@ createAdjustor(int cconv, StgStablePtr hptr, StgFunPtr wptr)
 
        adj_code[0x0c] = (unsigned char)0xff; /* jmp %eax */
        adj_code[0x0d] = (unsigned char)0xe0;
+       
+       execPage(adjustor,rtsTrue);
     }
 #endif
     break;
@@ -155,6 +234,8 @@ createAdjustor(int cconv, StgStablePtr hptr, StgFunPtr wptr)
 
        adj_code[0x0f] = (unsigned char)0xff; /* jmp *%eax */
        adj_code[0x10] = (unsigned char)0xe0; 
+
+       execPage(adjustor,rtsTrue);
     }
 #elif defined(sparc_TARGET_ARCH)
   /* Magic constant computed by inspecting the code length of the following
@@ -335,12 +416,91 @@ TODO: Depending on how much allocation overhead stgMallocBytes uses for
                        while(n--)
                        {
                                __asm__ volatile ("dcbf 0,%0\n\tsync\n\ticbi 0,%0"
-                                                   : : "g" (p));
+                                                   : : "r" (p));
                                p++;
                        }
                        __asm__ volatile ("sync\n\tisync");
                }
        }
+#elif defined(ia64_TARGET_ARCH)
+/*
+    Up to 8 inputs are passed in registers.  We flush the last two inputs to
+    the stack, initially into the 16-byte scratch region left by the caller.
+    We then shuffle the others along by 4 (taking 2 registers for ourselves
+    to save return address and previous function state - we need to come back
+    here on the way out to restore the stack, so this is a real function
+    rather than just a trampoline).
+    
+    The function descriptor we create contains the gp of the target function
+    so gp is already loaded correctly.
+
+       [MLX]       alloc r16=ar.pfs,10,2,0
+                   movl r17=wptr
+       [MII]       st8.spill [r12]=r38,8               // spill in6 (out4)
+                   mov r41=r37                         // out7 = in5 (out3)
+                   mov r40=r36;;                       // out6 = in4 (out2)
+       [MII]       st8.spill [r12]=r39                 // spill in7 (out5)
+                   mov.sptk b6=r17,50
+                   mov r38=r34;;                       // out4 = in2 (out0)
+       [MII]       mov r39=r35                         // out5 = in3 (out1)
+                   mov r37=r33                         // out3 = in1 (loc1)
+                   mov r36=r32                         // out2 = in0 (loc0)
+       [MLX]       adds r12=-24,r12                    // update sp
+                   movl r34=hptr;;                     // out0 = hptr
+       [MIB]       mov r33=r16                         // loc1 = ar.pfs
+                   mov r32=b0                          // loc0 = retaddr
+                   br.call.sptk.many b0=b6;;
+
+       [MII]       adds r12=-16,r12
+                   mov b0=r32
+                   mov.i ar.pfs=r33
+       [MFB]       nop.m 0x0
+                   nop.f 0x0
+                   br.ret.sptk.many b0;;
+*/
+
+/* These macros distribute a long constant into the two words of an MLX bundle */
+#define BITS(val,start,count)  (((val) >> (start)) & ((1 << (count))-1))
+#define MOVL_LOWORD(val)       (BITS(val,22,18) << 46)
+#define MOVL_HIWORD(val)       (BITS(val,40,23) | (BITS(val,0,7) << 36) | (BITS(val,7,9) << 50) \
+                               | (BITS(val,16,5) << 55) | (BITS(val,21,1) << 44) | BITS(val,63,1) << 59)
+
+    {
+       StgStablePtr stable;
+       IA64FunDesc *wdesc = (IA64FunDesc *)wptr;
+       StgWord64 wcode = wdesc->ip;
+       IA64FunDesc *fdesc;
+       StgWord64 *code;
+
+       /* we allocate on the Haskell heap since malloc'd memory isn't executable - argh */
+       adjustor = stgAllocStable(sizeof(IA64FunDesc)+18*8, &stable);
+
+       fdesc = (IA64FunDesc *)adjustor;
+       code = (StgWord64 *)(fdesc + 1);
+       fdesc->ip = (StgWord64)code;
+       fdesc->gp = wdesc->gp;
+
+       code[0]  = 0x0000058004288004 | MOVL_LOWORD(wcode);
+       code[1]  = 0x6000000220000000 | MOVL_HIWORD(wcode);
+       code[2]  = 0x029015d818984001;
+       code[3]  = 0x8401200500420094;
+       code[4]  = 0x886011d8189c0001;
+       code[5]  = 0x84011004c00380c0;
+       code[6]  = 0x0250210046013800;
+       code[7]  = 0x8401000480420084;
+       code[8]  = 0x0000233f19a06005 | MOVL_LOWORD((StgWord64)hptr);
+       code[9]  = 0x6000000440000000 | MOVL_HIWORD((StgWord64)hptr);
+       code[10] = 0x0200210020010811;
+       code[11] = 0x1080006800006200;
+       code[12] = 0x0000210018406000;
+       code[13] = 0x00aa021000038005;
+       code[14] = 0x000000010000001d;
+       code[15] = 0x0084000880000200;
+
+       /* save stable pointers in convenient form */
+       code[16] = (StgWord64)hptr;
+       code[17] = (StgWord64)stable;
+    }
 #else
     barf("adjustor creation not supported on this platform");
 #endif
@@ -394,11 +554,35 @@ freeHaskellFunctionPtr(void* ptr)
    return;
  }
  freeStablePtr(*((StgStablePtr*)((unsigned char*)ptr + 4*12)));
+#elif defined(ia64_TARGET_ARCH)
+ IA64FunDesc *fdesc = (IA64FunDesc *)ptr;
+ StgWord64 *code = (StgWord64 *)(fdesc+1);
+
+ if (fdesc->ip != (StgWord64)code) {
+   fprintf(stderr, "freeHaskellFunctionPtr: not for me, guv! %p\n", ptr);
+   return;
+ }
+ freeStablePtr((StgStablePtr)code[16]);
+ freeStablePtr((StgStablePtr)code[17]);
+ return;
 #else
  ASSERT(0);
 #endif
  *((unsigned char*)ptr) = '\0';
 
- free(ptr);
+ stgFree(ptr);
 }
 
+
+/*
+ * Function: initAdjustor()
+ *
+ * Perform initialisation of adjustor thunk layer (if needed.)
+ *
+ * TODO: Call this at RTS initialisation time.
+ */
+rtsBool
+initAdjustor(void)
+{
+    return execPage(__obscure_ccall_ret_code, rtsFalse);
+}