From 58cb62fe7b383ef5f91a35a89fb92ca3c5287b1c Mon Sep 17 00:00:00 2001
From: bunnei <bunneidev@gmail.com>
Date: Sun, 28 Dec 2014 16:18:52 -0500
Subject: [PATCH] armemu: Fix PKHTB to do an arithmetic shift and correctly
decode immediate field.
---
src/core/arm/interpreter/armemu.cpp | 18 +++++-------------
1 file changed, 5 insertions(+), 13 deletions(-)
diff --git a/src/core/arm/interpreter/armemu.cpp b/src/core/arm/interpreter/armemu.cpp
index 2873da897c..9c6602f097 100644
--- a/src/core/arm/interpreter/armemu.cpp
+++ b/src/core/arm/interpreter/armemu.cpp
@@ -3100,7 +3100,6 @@ mainswitch:
break;
case 0x68: /* Store Word, No WriteBack, Post Inc, Reg. */
- //ichfly PKHBT PKHTB todo check this
if ((instr & 0x70) == 0x10) { //pkhbt
u8 idest = BITS(12, 15);
u8 rfis = BITS(16, 19);
@@ -3109,18 +3108,11 @@ mainswitch:
state->Reg[idest] = (state->Reg[rfis] & 0xFFFF) | ((state->Reg[rlast] << ishi) & 0xFFFF0000);
break;
} else if ((instr & 0x70) == 0x50) { //pkhtb
- const u8 rd_idx = BITS(12, 15);
- const u8 rn_idx = BITS(16, 19);
- const u8 rm_idx = BITS(0, 3);
- const u8 imm5 = BITS(7, 11);
-
- ARMword val;
- if (imm5 >= 32)
- val = (state->Reg[rm_idx] >> 31);
- else
- val = (state->Reg[rm_idx] >> imm5);
-
- state->Reg[rd_idx] = (val & 0xFFFF) | ((state->Reg[rn_idx]) & 0xFFFF0000);
+ u8 rd_idx = BITS(12, 15);
+ u8 rn_idx = BITS(16, 19);
+ u8 rm_idx = BITS(0, 3);
+ u8 imm5 = BITS(7, 11) ? BITS(7, 11) : 31;
+ state->Reg[rd_idx] = ((static_cast<s32>(state->Reg[rm_idx]) >> imm5) & 0xFFFF) | ((state->Reg[rn_idx]) & 0xFFFF0000);
break;
} else if (BIT (4)) {
#ifdef MODE32