Re: [Qemu-devel] [PATCH 2/6] target-arm: fix Neon right shifts with shift amount == input width.

2011-02-15 Thread Christophe Lyon 

 -dest = src1  (tmp - 1); \
 +dest = src1  (-tmp - 1); \
 dest++; \
 dest = 1; \
 
 Again, these three lines have the same effect as dest = 0,
 so we can fold into the previous if().
 
 } else if (tmp  0) { \
 @@ -594,7 +594,7 @@ uint64_t HELPER(neon_rshl_s64)(uint64_t valop, uint64_t 
 shiftop)
 val = 0;
 } else if (shift  -64) {
 val = 63;
 
 You didn't change this case, but it is the wrong answer:
 should be 0.
 
 -} else if (shift == -63) {
 +} else if (shift == -64) {
 val = 63;
 val++;
 val = 1;
 
 Always results in 0.
 


Oops sorry, in these 3 cases, I just fixed obvious typos but didn't question 
the actual code.

Re: [Qemu-devel] [PATCH 2/6] target-arm: fix Neon right shifts with shift amount == input width.

2011-02-14 Thread Peter Maydell 
On 11 February 2011 15:10,  christophe.l...@st.com wrote:
 From: Christophe Lyon christophe.l...@st.com

 Fix rshl helpers (s8, s16, s64, u8, u16)

 Signed-off-by: Christophe Lyon christophe.l...@st.com
 ---
  target-arm/neon_helper.c |    6 +++---
  1 files changed, 3 insertions(+), 3 deletions(-)

 diff --git a/target-arm/neon_helper.c b/target-arm/neon_helper.c
 index 3f1f3d4..1ac362f 100644
 --- a/target-arm/neon_helper.c
 +++ b/target-arm/neon_helper.c
 @@ -548,7 +548,7 @@ uint64_t HELPER(neon_shl_s64)(uint64_t valop, uint64_t 
 shiftop)
     } else if (tmp  -(ssize_t)sizeof(src1) * 8) { \
         dest = src1  (sizeof(src1) * 8 - 1); \
     } else if (tmp == -(ssize_t)sizeof(src1) * 8) { \
 -        dest = src1  (tmp - 1); \
 +        dest = src1  (-tmp - 1); \
         dest++; \
         dest = 1; \

Again, these three lines have the same effect as dest = 0,
so we can fold into the previous if().

     } else if (tmp  0) { \
 @@ -594,7 +594,7 @@ uint64_t HELPER(neon_rshl_s64)(uint64_t valop, uint64_t 
 shiftop)
         val = 0;
     } else if (shift  -64) {
         val = 63;

You didn't change this case, but it is the wrong answer:
should be 0.

 -    } else if (shift == -63) {
 +    } else if (shift == -64) {
         val = 63;
         val++;
         val = 1;

Always results in 0.

-- PMM

[Qemu-devel] [PATCH 2/6] target-arm: fix Neon right shifts with shift amount == input width.

2011-02-11 Thread christophe.lyon 
From: Christophe Lyon christophe.l...@st.com

Fix rshl helpers (s8, s16, s64, u8, u16)

Signed-off-by: Christophe Lyon christophe.l...@st.com
---
 target-arm/neon_helper.c |6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/target-arm/neon_helper.c b/target-arm/neon_helper.c
index 3f1f3d4..1ac362f 100644
--- a/target-arm/neon_helper.c
+++ b/target-arm/neon_helper.c
@@ -548,7 +548,7 @@ uint64_t HELPER(neon_shl_s64)(uint64_t valop, uint64_t 
shiftop)
 } else if (tmp  -(ssize_t)sizeof(src1) * 8) { \
 dest = src1  (sizeof(src1) * 8 - 1); \
 } else if (tmp == -(ssize_t)sizeof(src1) * 8) { \
-dest = src1  (tmp - 1); \
+dest = src1  (-tmp - 1); \
 dest++; \
 dest = 1; \
 } else if (tmp  0) { \
@@ -594,7 +594,7 @@ uint64_t HELPER(neon_rshl_s64)(uint64_t valop, uint64_t 
shiftop)
 val = 0;
 } else if (shift  -64) {
 val = 63;
-} else if (shift == -63) {
+} else if (shift == -64) {
 val = 63;
 val++;
 val = 1;
@@ -622,7 +622,7 @@ uint64_t HELPER(neon_rshl_s64)(uint64_t valop, uint64_t 
shiftop)
 tmp  -(ssize_t)sizeof(src1) * 8) { \
 dest = 0; \
 } else if (tmp == -(ssize_t)sizeof(src1) * 8) { \
-dest = src1  (tmp - 1); \
+dest = src1  (-tmp - 1); \
 } else if (tmp  0) { \
 dest = (src1 + (1  (-1 - tmp)))  -tmp; \
 } else { \
-- 
1.7.2.3