#include "Rts.h"
#include "RtsUtils.h"
#include "RtsFlags.h"
+
#include <stdlib.h>
/* Heavily arch-specific, I'm afraid.. */
adj_code[0x10] = (unsigned char)0xe0;
}
#elif defined(sparc_TARGET_ARCH)
- /* Magic constant computed by inspecting the code length of
- the following assembly language snippet
- (offset and machine code prefixed):
-
- <00>: BA 10 00 1B mov %i3, %i5
- <04>: B8 10 00 1A mov %i2, %i4
- <08>: B6 10 00 19 mov %i1, %i3
- <0c>: B4 10 00 18 mov %i0, %i2
- <10>: 13 00 3f fb sethi %hi(0x00ffeffa), %o1 # load up wptr (1 of 2)
- <14>: 11 37 ab 6f sethi %hi(0xdeadbeef), %o0 # load up hptr (1 of 2)
- <18>: 81 c2 63 fa jmp %o1+%lo(0x00ffeffa) # jump to wptr (load 2 of 2)
- <1c>: 90 12 22 ef or %o0, %lo(0xdeadbeef), %o0 # load up hptr (2 of 2)
- # [in delay slot]
- <20>: de ad be ef # Place the value of the StgStablePtr somewhere readable
-
- ccall'ing on a SPARC leaves little to be performed by the caller.
- The callee shifts the window on entry and restores it on exit.
- Input paramters and results are passed via registers. (%o0 in the
- code above contains the input paramter to wptr.) The return address
- is stored in %o7/%i7. Since we don't shift the window in this code,
- the return address is preserved and wptr will return to our caller.
-
- JRS, 21 Aug 01: the above para is a fiction. The caller passes
- args in %i0 .. %i5 and then the rest at [%sp+92]. We want to
- tailjump to wptr, passing hptr as the new first arg, and a dummy
- second arg, which would be where the return address is on x86.
- That means we have to shuffle the original caller's args along by
- two.
-
- We do a half-correct solution which works only if the original
- caller passed 4 or fewer arg words. Move %i0 .. %i3 into %i3
- .. %i6, so we can park hptr in %i0 and a bogus arg in %i1. The
- fully correct solution would be to subtract 8 from %sp and then
- place %i4 and %i5 at [%sp+92] and [%sp+96] respectively. This
- machinery should then work in all cases. (Or would it? Perhaps
- it would trash parts of the caller's frame. Dunno).
-
- SUP, 25 Apr 02: We are quite lucky to push a multiple of 8 bytes in
- front of the existing arguments, because %sp must stay double-word
- aligned at all times, see: http://www.sparc.org/standards/psABI3rd.pdf
- Although we extend the *caller's* stack frame, this shouldn't cause
- any problems for a C-like caller: alloca is implemented similarly, and
- local variables should be accessed via %fp, not %sp. In a nutshell:
- This should work. (Famous last words! :-)
+ /* Magic constant computed by inspecting the code length of the following
+ assembly language snippet (offset and machine code prefixed):
+
+ <00>: 9C23A008 sub %sp, 8, %sp ! make room for %o4/%o5 in caller's frame
+ <04>: DA23A060 st %o5, [%sp + 96] ! shift registers by 2 positions
+ <08>: D823A05C st %o4, [%sp + 92]
+ <0C>: 9A10000B mov %o3, %o5
+ <10>: 9810000A mov %o2, %o4
+ <14>: 96100009 mov %o1, %o3
+ <18>: 94100008 mov %o0, %o2
+ <1C>: 13000000 sethi %hi(wptr), %o1 ! load up wptr (1 of 2)
+ <20>: 11000000 sethi %hi(hptr), %o0 ! load up hptr (1 of 2)
+ <24>: 81C26000 jmp %o1 + %lo(wptr) ! jump to wptr (load 2 of 2)
+ <28>: 90122000 or %o0, %lo(hptr), %o0 ! load up hptr (2 of 2, delay slot)
+ <2C> 00000000 ! place for getting hptr back easily
+
+ ccall'ing on SPARC is easy, because we are quite lucky to push a
+ multiple of 8 bytes (1 word hptr + 1 word dummy arg) in front of the
+ existing arguments (note that %sp must stay double-word aligned at
+ all times, see ABI spec at http://www.sparc.org/standards/psABI3rd.pdf).
+ To do this, we extend the *caller's* stack frame by 2 words and shift
+ the output registers used for argument passing (%o0 - %o5, we are a *leaf*
+ procedure because of the tail-jump) by 2 positions. This makes room in
+ %o0 and %o1 for the additinal arguments, namely hptr and a dummy (used
+ for destination addr of jump on SPARC, return address on x86, ...). This
+ shouldn't cause any problems for a C-like caller: alloca is implemented
+ similarly, and local variables should be accessed via %fp, not %sp. In a
+ nutshell: This should work! (Famous last words! :-)
*/
- if ((adjustor = stgMallocBytes(4*(8+1), "createAdjustor")) != NULL) {
- unsigned long *const adj_code = (unsigned long *)adjustor;
-
- /* mov %o3, %o5 */
- adj_code[0] = (unsigned long)0x9A10000B;
- /* mov %o2, %o4 */
- adj_code[1] = (unsigned long)0x9810000A;
- /* mov %o1, %o3 */
- adj_code[2] = (unsigned long)0x96100009;
- /* mov %o0, %o2 */
- adj_code[3] = (unsigned long)0x94100008;
-
- /* sethi %hi(wptr), %o1 */
- adj_code[4] = (unsigned long)0x13000000;
- adj_code[4] |= ((unsigned long)wptr) >> 10;
-
- /* sethi %hi(hptr), %o0 */
- adj_code[5] = (unsigned long)0x11000000;
- adj_code[5] |= ((unsigned long)hptr) >> 10;
-
- /* jmp %o1+%lo(wptr) */
- adj_code[6] = (unsigned long)0x81c26000;
- adj_code[6] |= ((unsigned long)wptr) & 0x000003ff;
-
- /* or %o0, %lo(hptr), %o0 */
- adj_code[7] = (unsigned long)0x90122000;
- adj_code[7] |= ((unsigned long)hptr) & 0x000003ff;
-
- adj_code[8] = (StgStablePtr)hptr;
-
- /* flush cache */
- asm("flush %0" : : "r" (adj_code ));
- asm("flush %0" : : "r" (adj_code + 2));
- asm("flush %0" : : "r" (adj_code + 4));
- asm("flush %0" : : "r" (adj_code + 6));
-
- /* max. 5 instructions latency, and we need at >= 1 for returning */
- asm("nop");
- asm("nop");
- asm("nop");
- asm("nop");
+ if ((adjustor = stgMallocBytes(4*(11+1), "createAdjustor")) != NULL) {
+ unsigned long *const adj_code = (unsigned long *)adjustor;
+
+ adj_code[ 0] = 0x9C23A008UL; /* sub %sp, 8, %sp */
+ adj_code[ 1] = 0xDA23A060UL; /* st %o5, [%sp + 96] */
+ adj_code[ 2] = 0xD823A05CUL; /* st %o4, [%sp + 92] */
+ adj_code[ 3] = 0x9A10000BUL; /* mov %o3, %o5 */
+ adj_code[ 4] = 0x9810000AUL; /* mov %o2, %o4 */
+ adj_code[ 5] = 0x96100009UL; /* mov %o1, %o3 */
+ adj_code[ 6] = 0x94100008UL; /* mov %o0, %o2 */
+ adj_code[ 7] = 0x13000000UL; /* sethi %hi(wptr), %o1 */
+ adj_code[ 7] |= ((unsigned long)wptr) >> 10;
+ adj_code[ 8] = 0x11000000UL; /* sethi %hi(hptr), %o0 */
+ adj_code[ 8] |= ((unsigned long)hptr) >> 10;
+ adj_code[ 9] = 0x81C26000UL; /* jmp %o1 + %lo(wptr) */
+ adj_code[ 9] |= ((unsigned long)wptr) & 0x000003FFUL;
+ adj_code[10] = 0x90122000UL; /* or %o0, %lo(hptr), %o0 */
+ adj_code[10] |= ((unsigned long)hptr) & 0x000003FFUL;
+
+ adj_code[11] = (unsigned long)hptr;
+
+ /* flush cache */
+ asm("flush %0" : : "r" (adj_code ));
+ asm("flush %0" : : "r" (adj_code + 2));
+ asm("flush %0" : : "r" (adj_code + 4));
+ asm("flush %0" : : "r" (adj_code + 6));
+ asm("flush %0" : : "r" (adj_code + 10));
+
+ /* max. 5 instructions latency, and we need at >= 1 for returning */
+ asm("nop");
+ asm("nop");
+ asm("nop");
+ asm("nop");
}
#elif defined(alpha_TARGET_ARCH)
/* Magic constant computed by inspecting the code length of
freeStablePtr(*((StgStablePtr*)((unsigned char*)ptr + 0x02)));
}
#elif defined(sparc_TARGET_ARCH)
- if ( *(unsigned long*)ptr != 0x9A10000B ) {
+ if ( *(unsigned long*)ptr != 0x9C23A008UL ) {
fprintf(stderr, "freeHaskellFunctionPtr: not for me, guv! %p\n", ptr);
return;
}
/* Free the stable pointer first..*/
- freeStablePtr(*((StgStablePtr*)((unsigned long*)ptr + 8)));
+ freeStablePtr(*((StgStablePtr*)((unsigned long*)ptr + 11)));
#elif defined(alpha_TARGET_ARCH)
if ( *(StgWord64*)ptr != 0xa77b0018a61b0010L ) {
fprintf(stderr, "freeHaskellFunctionPtr: not for me, guv! %p\n", ptr);
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