Patchwork [02/12] target-arm: Fix mixup in decoding of saturating add and sub

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Submitter Peter Maydell
Date Nov. 23, 2010, 6:53 p.m.
Message ID <1290538431-13170-3-git-send-email-peter.maydell@linaro.org>
Download mbox | patch
Permalink /patch/72735/
State New
Headers show

Comments

Peter Maydell - Nov. 23, 2010, 6:53 p.m.
From: Johan Bengtsson <teofrastius@gmail.com>

The thumb2 decoder contained a mixup between the bit controlling
doubling and the bit controlling if the operation was an add or a sub.

Signed-off-by: Johan Bengtsson <teofrastius@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target-arm/translate.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
Nathan Froyd - Nov. 29, 2010, 5:01 p.m.
On Tue, Nov 23, 2010 at 06:53:41PM +0000, Peter Maydell wrote:
> From: Johan Bengtsson <teofrastius@gmail.com>
> 
> The thumb2 decoder contained a mixup between the bit controlling
> doubling and the bit controlling if the operation was an add or a sub.
> 
> Signed-off-by: Johan Bengtsson <teofrastius@gmail.com>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Reviewed-by: Nathan Froyd <froydnj@codesourcery.com>

-Nathan

Patch

diff --git a/target-arm/translate.c b/target-arm/translate.c
index 183928b..947de6d 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -7713,9 +7713,9 @@  static int disas_thumb2_insn(CPUState *env, DisasContext *s, uint16_t insn_hw1)
                 /* Saturating add/subtract.  */
                 tmp = load_reg(s, rn);
                 tmp2 = load_reg(s, rm);
-                if (op & 2)
-                    gen_helper_double_saturate(tmp, tmp);
                 if (op & 1)
+                    gen_helper_double_saturate(tmp, tmp);
+                if (op & 2)
                     gen_helper_sub_saturate(tmp, tmp2, tmp);
                 else
                     gen_helper_add_saturate(tmp, tmp, tmp2);