qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Qemu-devel] [PATCH] target-arm: Decode SETEND correctly in Thumb


From: Peter Maydell
Subject: [Qemu-devel] [PATCH] target-arm: Decode SETEND correctly in Thumb
Date: Tue, 13 Mar 2012 14:45:08 +0000

Decode the SETEND instruction correctly in Thumb mode,
rather than accidentally treating it like CPS. We don't
support BE8 mode, but this change brings the Thumb mode
in to line with behaviour in ARM mode: 'SETEND BE' is
not supported and will provoke an UNDEF exception, but
'SETEND LE' is correctly handled as a no-op.

Signed-off-by: Peter Maydell <address@hidden>
Reported-by: Daniel Forsgren <address@hidden>
---
This is one of those patches where I wasn't sure whether to try
to split it into a whitespace-only part and a significant-change
part. Most of this is (a) indenting existing code another notch
for the extra switch statement and (b) adding braces to placate
checkpatch.

 target-arm/translate.c |   63 ++++++++++++++++++++++++++++++-----------------
 1 files changed, 40 insertions(+), 23 deletions(-)

diff --git a/target-arm/translate.c b/target-arm/translate.c
index 280bfca..3196619 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -9704,32 +9704,49 @@ static void disas_thumb_insn(CPUState *env, 
DisasContext *s)
             store_reg(s, rd, tmp);
             break;
 
-        case 6: /* cps */
-            ARCH(6);
-            if (IS_USER(s))
+        case 6:
+            switch ((insn >> 5) & 7) {
+            case 2:
+                /* setend */
+                ARCH(6);
+                if (insn & (1 << 3)) {
+                    /* BE8 mode not implemented.  */
+                    goto illegal_op;
+                }
                 break;
-            if (IS_M(env)) {
-                tmp = tcg_const_i32((insn & (1 << 4)) != 0);
-                /* FAULTMASK */
-                if (insn & 1) {
-                    addr = tcg_const_i32(19);
-                    gen_helper_v7m_msr(cpu_env, addr, tmp);
-                    tcg_temp_free_i32(addr);
+            case 3:
+                /* cps */
+                ARCH(6);
+                if (IS_USER(s)) {
+                    break;
                 }
-                /* PRIMASK */
-                if (insn & 2) {
-                    addr = tcg_const_i32(16);
-                    gen_helper_v7m_msr(cpu_env, addr, tmp);
-                    tcg_temp_free_i32(addr);
+                if (IS_M(env)) {
+                    tmp = tcg_const_i32((insn & (1 << 4)) != 0);
+                    /* FAULTMASK */
+                    if (insn & 1) {
+                        addr = tcg_const_i32(19);
+                        gen_helper_v7m_msr(cpu_env, addr, tmp);
+                        tcg_temp_free_i32(addr);
+                    }
+                    /* PRIMASK */
+                    if (insn & 2) {
+                        addr = tcg_const_i32(16);
+                        gen_helper_v7m_msr(cpu_env, addr, tmp);
+                        tcg_temp_free_i32(addr);
+                    }
+                    tcg_temp_free_i32(tmp);
+                    gen_lookup_tb(s);
+                } else {
+                    if (insn & (1 << 4)) {
+                        shift = CPSR_A | CPSR_I | CPSR_F;
+                    } else {
+                        shift = 0;
+                    }
+                    gen_set_psr_im(s, ((insn & 7) << 6), 0, shift);
                 }
-                tcg_temp_free_i32(tmp);
-                gen_lookup_tb(s);
-            } else {
-                if (insn & (1 << 4))
-                    shift = CPSR_A | CPSR_I | CPSR_F;
-                else
-                    shift = 0;
-                gen_set_psr_im(s, ((insn & 7) << 6), 0, shift);
+                break;
+            default:
+                goto undef;
             }
             break;
 
-- 
1.7.1




reply via email to

[Prev in Thread] Current Thread [Next in Thread]