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

Thanks to Sergey Kaplun. #1422 #1418

1 files changed, 5 insertions, 1 deletions

diff --git a/src/vm_mips.dasc b/src/vm_mips.dasc
index 5063e7c6..9a39edd6 100644
--- a/src/vm_mips.dasc
+++ b/src/vm_mips.dasc
@@ -3566,7 +3566,8 @@ static void build_ins(BuildCtx *ctx, BCOp op, int defop)
     |   addu RA, BASE, RA
     |  bne SFARG1HI, TISNUM, >2
     |.  lw SFARG1LO, LO(RB)
-    |  lui TMP1, 0x8000
+    |  beqz SFARG1LO, >3
+    |.  lui TMP1, 0x8000
     |  beq SFARG1LO, TMP1, ->vmeta_unm  // Meta handler deals with -2^31.
     |.  negu SFARG1LO, SFARG1LO
     |1:
@@ -3580,6 +3581,9 @@ static void build_ins(BuildCtx *ctx, BCOp op, int defop)
     |.  lui TMP1, 0x8000
     |  b <1
     |.  xor SFARG1HI, SFARG1HI, TMP1
+    |3:
+    |  b <1
+    |.  lui SFARG1HI, 0x8000    // -0.
     break;
   case BC_LEN:
     |  // RA = dst*8, RD = src*8