[Qemu-devel] [PATCH v3] target-arm: fix neon shift helper functions

[juha . riihimaki]

From: Juha Riihimäki <address@hidden>

Current code is broken at least on recent compilers, comparison
between signed and unsigned types yield incorrect code and render
the neon shift helper functions defunct. This is the third revision
of this patch, casting all comparisons with the sizeof operator to
signed ssize_t type to force comparisons to be between signed integral
types.

Signed-off-by: Juha Riihimäki <address@hidden>
---
 target-arm/neon_helper.c |   26 ++++++++++++++------------
 1 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/target-arm/neon_helper.c b/target-arm/neon_helper.c
index f32ecd6..5e6452b 100644
--- a/target-arm/neon_helper.c
+++ b/target-arm/neon_helper.c
@@ -392,7 +392,8 @@ NEON_VOP(abd_u32, neon_u32, 1)
 #define NEON_FN(dest, src1, src2) do { \
     int8_t tmp; \
     tmp = (int8_t)src2; \
-    if (tmp >= sizeof(src1) * 8 || tmp <= -sizeof(src1) * 8) { \
+    if (tmp >= (ssize_t)sizeof(src1) * 8 || \
+        tmp <= -(ssize_t)sizeof(src1) * 8) { \
         dest = 0; \
     } else if (tmp < 0) { \
         dest = src1 >> -tmp; \
@@ -420,9 +421,9 @@ uint64_t HELPER(neon_shl_u64)(uint64_t val, uint64_t 
shiftop)
 #define NEON_FN(dest, src1, src2) do { \
     int8_t tmp; \
     tmp = (int8_t)src2; \
-    if (tmp >= sizeof(src1) * 8) { \
+    if (tmp >= (ssize_t)sizeof(src1) * 8) { \
         dest = 0; \
-    } else if (tmp <= -sizeof(src1) * 8) { \
+    } else if (tmp <= -(ssize_t)sizeof(src1) * 8) { \
         dest = src1 >> (sizeof(src1) * 8 - 1); \
     } else if (tmp < 0) { \
         dest = src1 >> -tmp; \
@@ -453,11 +454,11 @@ uint64_t HELPER(neon_shl_s64)(uint64_t valop, uint64_t 
shiftop)
 #define NEON_FN(dest, src1, src2) do { \
     int8_t tmp; \
     tmp = (int8_t)src2; \
-    if (tmp >= sizeof(src1) * 8) { \
+    if (tmp >= (ssize_t)sizeof(src1) * 8) { \
         dest = 0; \
-    } else if (tmp < -sizeof(src1) * 8) { \
+    } else if (tmp < -(ssize_t)sizeof(src1) * 8) { \
         dest = src1 >> (sizeof(src1) * 8 - 1); \
-    } else if (tmp == -sizeof(src1) * 8) { \
+    } else if (tmp == -(ssize_t)sizeof(src1) * 8) { \
         dest = src1 >> (tmp - 1); \
         dest++; \
         dest >>= 1; \
@@ -494,9 +495,10 @@ uint64_t HELPER(neon_rshl_s64)(uint64_t valop, uint64_t 
shiftop)
 #define NEON_FN(dest, src1, src2) do { \
     int8_t tmp; \
     tmp = (int8_t)src2; \
-    if (tmp >= sizeof(src1) * 8 || tmp < -sizeof(src1) * 8) { \
+    if (tmp >= (ssize_t)sizeof(src1) * 8 || \
+        tmp < -(ssize_t)sizeof(src1) * 8) { \
         dest = 0; \
-    } else if (tmp == -sizeof(src1) * 8) { \
+    } else if (tmp == -(ssize_t)sizeof(src1) * 8) { \
         dest = src1 >> (tmp - 1); \
     } else if (tmp < 0) { \
         dest = (src1 + (1 << (-1 - tmp))) >> -tmp; \
@@ -528,14 +530,14 @@ uint64_t HELPER(neon_rshl_u64)(uint64_t val, uint64_t 
shiftop)
 #define NEON_FN(dest, src1, src2) do { \
     int8_t tmp; \
     tmp = (int8_t)src2; \
-    if (tmp >= sizeof(src1) * 8) { \
+    if (tmp >= (ssize_t)sizeof(src1) * 8) { \
         if (src1) { \
             SET_QC(); \
             dest = ~0; \
         } else { \
             dest = 0; \
         } \
-    } else if (tmp <= -sizeof(src1) * 8) { \
+    } else if (tmp <= -(ssize_t)sizeof(src1) * 8) { \
         dest = 0; \
     } else if (tmp < 0) { \
         dest = src1 >> -tmp; \
@@ -579,11 +581,11 @@ uint64_t HELPER(neon_qshl_u64)(CPUState *env, uint64_t 
val, uint64_t shiftop)
 #define NEON_FN(dest, src1, src2) do { \
     int8_t tmp; \
     tmp = (int8_t)src2; \
-    if (tmp >= sizeof(src1) * 8) { \
+    if (tmp >= (ssize_t)sizeof(src1) * 8) { \
         if (src1) \
             SET_QC(); \
         dest = src1 >> 31; \
-    } else if (tmp <= -sizeof(src1) * 8) { \
+    } else if (tmp <= -(ssize_t)sizeof(src1) * 8) { \
         dest = src1 >> 31; \
     } else if (tmp < 0) { \
         dest = src1 >> -tmp; \
-- 
1.6.5