From a44388967763d0f7f5f78dfd71703437afa69fc0 Mon Sep 17 00:00:00 2001
From: Mike Pall <mike>
Date: Wed, 10 Feb 2016 18:51:02 +0100
Subject: [PATCH] Don't allocate unused 2nd result register in JIT compiler
 backend.

---
 src/lj_asm_arm.h  | 2 +-
 src/lj_asm_mips.h | 2 +-
 src/lj_asm_ppc.h  | 2 +-
 src/lj_asm_x86.h  | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/lj_asm_arm.h b/src/lj_asm_arm.h
index 9e4cf436..ba65f45b 100644
--- a/src/lj_asm_arm.h
+++ b/src/lj_asm_arm.h
@@ -426,7 +426,7 @@ static void asm_gencall(ASMState *as, const CCallInfo *ci, IRRef *args)
 static void asm_setupresult(ASMState *as, IRIns *ir, const CCallInfo *ci)
 {
   RegSet drop = RSET_SCRATCH;
-  int hiop = ((ir+1)->o == IR_HIOP);
+  int hiop = ((ir+1)->o == IR_HIOP && !irt_isnil((ir+1)->t));
   if (ra_hasreg(ir->r))
     rset_clear(drop, ir->r);  /* Dest reg handled below. */
   if (hiop && ra_hasreg((ir+1)->r))
diff --git a/src/lj_asm_mips.h b/src/lj_asm_mips.h
index 78bd26d5..8cdd913b 100644
--- a/src/lj_asm_mips.h
+++ b/src/lj_asm_mips.h
@@ -291,7 +291,7 @@ static void asm_gencall(ASMState *as, const CCallInfo *ci, IRRef *args)
 static void asm_setupresult(ASMState *as, IRIns *ir, const CCallInfo *ci)
 {
   RegSet drop = RSET_SCRATCH;
-  int hiop = ((ir+1)->o == IR_HIOP);
+  int hiop = ((ir+1)->o == IR_HIOP && !irt_isnil((ir+1)->t));
   if ((ci->flags & CCI_NOFPRCLOBBER))
     drop &= ~RSET_FPR;
   if (ra_hasreg(ir->r))
diff --git a/src/lj_asm_ppc.h b/src/lj_asm_ppc.h
index 2c5d74a8..e6129032 100644
--- a/src/lj_asm_ppc.h
+++ b/src/lj_asm_ppc.h
@@ -298,7 +298,7 @@ static void asm_gencall(ASMState *as, const CCallInfo *ci, IRRef *args)
 static void asm_setupresult(ASMState *as, IRIns *ir, const CCallInfo *ci)
 {
   RegSet drop = RSET_SCRATCH;
-  int hiop = ((ir+1)->o == IR_HIOP);
+  int hiop = ((ir+1)->o == IR_HIOP && !irt_isnil((ir+1)->t));
   if ((ci->flags & CCI_NOFPRCLOBBER))
     drop &= ~RSET_FPR;
   if (ra_hasreg(ir->r))
diff --git a/src/lj_asm_x86.h b/src/lj_asm_x86.h
index 0b6b2d4a..a79be4e6 100644
--- a/src/lj_asm_x86.h
+++ b/src/lj_asm_x86.h
@@ -531,7 +531,7 @@ static void asm_gencall(ASMState *as, const CCallInfo *ci, IRRef *args)
 static void asm_setupresult(ASMState *as, IRIns *ir, const CCallInfo *ci)
 {
   RegSet drop = RSET_SCRATCH;
-  int hiop = (LJ_32 && (ir+1)->o == IR_HIOP);
+  int hiop = (LJ_32 && (ir+1)->o == IR_HIOP && !irt_isnil((ir+1)->t));
   if ((ci->flags & CCI_NOFPRCLOBBER))
     drop &= ~RSET_FPR;
   if (ra_hasreg(ir->r))