DUALNUM: Improve/fix edge cases of unary minus.HEADv2.1

Thanks to Sergey Kaplun. #1422 #1418

1 files changed, 5 insertions, 0 deletions

diff --git a/src/vm_x86.dasc b/src/vm_x86.dasc
index d7d82b32..7e3d68a0 100644
--- a/src/vm_x86.dasc
+++ b/src/vm_x86.dasc
@@ -3856,11 +3856,16 @@ static void build_ins(BuildCtx *ctx, BCOp op, int defop)
     |  checkint RD, >5
     |  mov RB, [BASE+RD*8]
     |  neg RB
+    |  jz >3
     |  jo >4
     |  mov dword [BASE+RA*8+4], LJ_TISNUM
+    |8:
     |  mov dword [BASE+RA*8], RB
     |9:
     |  ins_next
+    |3:
+    |  mov dword [BASE+RA*8+4], 0x80000000  // -0.
+    |  jmp <8
     |4:
     |  mov dword [BASE+RA*8+4], 0x41e00000  // 2^31.
     |  mov dword [BASE+RA*8], 0