Implement yield from C hooks.

Get number of multiple results from C frame.
Add lj_cont_hook: restores multres and dispatch to static ins.
Can use fastcall for lj_dispatch_ins() now.

1 files changed, 12 insertions, 17 deletions

diff --git a/src/buildvm_x86.dasc b/src/buildvm_x86.dasc
index 5ff76a55..952fc9d6 100644
--- a/src/buildvm_x86.dasc
+++ b/src/buildvm_x86.dasc
@@ -618,13 +618,11 @@ static void build_subroutines(BuildCtx *ctx, int cmov, int sse)
   |->vm_unwind_c:                       // Unwind C stack, return from vm_pcall.
   |  // (void *cframe, int errcode)
   |.if X64
-  |  and CARG1, CFRAME_RAWMASK
   |  mov eax, CARG2d                    // Error return status for vm_pcall.
   |  mov rsp, CARG1
   |.else
   |  mov ecx, [esp+4]
   |  mov eax, [esp+8]                   // Error return status for vm_pcall.
-  |  and ecx, CFRAME_RAWMASK
   |  mov esp, ecx
   |.endif
   |  mov L:RB, SAVE_L
@@ -2618,24 +2616,15 @@ static void build_subroutines(BuildCtx *ctx, int cmov, int sse)
   |  test RDL, LUA_MASKLINE
   |  jz >5
   |1:
-  |.if X64
-  |  mov L:RB, SAVE_L
-  |  mov L:RB->base, BASE               // Caveat: CARG2d/CARG3d may be BASE.
-  |  mov CARG3d, NRESULTS               // Dynamic top for *M instructions.
-  |  mov CARG2d, PC
-  |  mov CARG1d, L:RB
-  |.else
   |  mov L:RB, SAVE_L
-  |  mov RD, NRESULTS                   // Dynamic top for *M instructions.
-  |  mov ARG3, RD
   |  mov L:RB->base, BASE
-  |  mov ARG2, PC
-  |  mov ARG1, L:RB
-  |.endif
+  |  mov FCARG2, PC                     // Caveat: FCARG2 == BASE
+  |  mov FCARG1, L:RB
   |  // SAVE_PC must hold the _previous_ PC. The callee updates it with PC.
-  |  call extern lj_dispatch_ins  // (lua_State *L, BCIns *pc, int nres)
-  |4:
+  |  call extern lj_dispatch_ins@8      // (lua_State *L, BCIns *pc)
+  |3:
   |  mov BASE, L:RB->base
+  |4:
   |  movzx RA, PC_RA
   |5:
   |  movzx OP, PC_OP
@@ -2646,6 +2635,12 @@ static void build_subroutines(BuildCtx *ctx, int cmov, int sse)
   |  jmp aword [DISPATCH+OP*4+GG_DISP_STATIC*4] // Re-dispatch to static ins.
   |.endif
   |
+  |->cont_hook:                         // Continue from hook yield.
+  |  add PC, 4
+  |  mov RA, [RB-24]
+  |  mov NRESULTS, RA                   // Restore NRESULTS for *M ins.
+  |  jmp <4
+  |
   |->vm_hotloop:                        // Hot loop counter underflow.
 #if LJ_HASJIT
   |.if X64
@@ -2658,7 +2653,7 @@ static void build_subroutines(BuildCtx *ctx, int cmov, int sse)
   |  mov [DISPATCH+DISPATCH_J(L)], L:RB
   |  mov SAVE_PC, PC
   |  call extern lj_trace_hot@8         // (jit_State *J, const BCIns *pc)
-  |  jmp <4
+  |  jmp <3
   |.endif
 #endif
   |