http://sourceware.org/ml/gdb-patches/2012-11/msg00312.html

gdb/ChangeLog
        * valarith.c (value_vector_widen): New function for replicating a
        scalar into a vector.
        (value_binop): Use value_vector_widen to widen scalar to vector
        rather than casting, this better matches gcc C behaviour.
        * valops.c (value_casst): Update logic for casting between vector
        types, and for casting from scalar to vector, try to match gcc C
        behaviour.
        * value.h (value_vector_widen): Declare.
        * opencl-lang.c (opencl_value_cast): New opencl specific casting
        function, handle special case for casting scalar to vector.
        (opencl_relop): Use opencl_value_cast.
        (evaluate_subexp_opencl): Use opencl_value_cast instead of
        value_cast, and handle BINOP_ASSIGN, UNOP_CAST, and UNOP_CAST_TYPE
        in order to use opencl_value_cast.

gdb/testsuite/ChangeLog
        * gdb.base/gnu_vector.c: New variable for use in tests.
        * gdb.base/gnu_vector.exp: Update and extend tests to reflect
        changes in scalar to vector casting and widening.
        * gdb.python/py-type.c: New variables for use in tests.
        * gdb.python/py-type.exp: Update vector related tests to reflect
        changes in scalar to vector casting and widening.

2 files changed, 41 insertions, 16 deletions

diff --git a/gdb/testsuite/gdb.base/gnu_vector.c b/gdb/testsuite/gdb.base/gnu_vector.c
index 76eefed..062aadb 100644
--- a/gdb/testsuite/gdb.base/gnu_vector.c
+++ b/gdb/testsuite/gdb.base/gnu_vector.c
@@ -31,6 +31,7 @@ int ia = 2;
 int ib = 1;
 float fa = 2;
 float fb = 1;
+long long lla __attribute__ ((mode(DI))) = 0x0000000100000001ll;
 char4 c4 = {1, 2, 3, 4};
 int4 i4a = {2, 4, 8, 16};
 int4 i4b = {1, 2, 8, 4};
diff --git a/gdb/testsuite/gdb.base/gnu_vector.exp b/gdb/testsuite/gdb.base/gnu_vector.exp
index 5f5b40f..f65627b 100644
--- a/gdb/testsuite/gdb.base/gnu_vector.exp
+++ b/gdb/testsuite/gdb.base/gnu_vector.exp
@@ -82,32 +82,52 @@ gdb_test "print f4a / f4b" "\\\$$decimal = \\{2, 2, 1, 4\\}"
 gdb_test "print +f4a" "\\\$$decimal = \\{2, 4, 8, 16\\}"
 gdb_test "print -f4a" "\\\$$decimal = \\{-2, -4, -8, -16\\}"
 
-# Test scalar to vector widening
-gdb_test "print (int2) 1" "\\\$$decimal = \\{1, 1\\}"
-gdb_test "print (longlong2) 2" "\\\$$decimal = \\{2, 2\\}"
-gdb_test "print (float2) 3" "\\\$$decimal = \\{3, 3\\}"
-gdb_test "print (double2) 4" "\\\$$decimal = \\{4, 4\\}"
-gdb_test "print (char4) 12" "\\\$$decimal = \\{12, 12, 12, 12\\}"
-gdb_test "print (uint4) ia" "\\\$$decimal = \\{2, 2, 2, 2\\}"
-gdb_test "print (int4) -3" "\\\$$decimal = \\{-3, -3, -3, -3\\}"
-gdb_test "print (float4) 4" "\\\$$decimal = \\{4, 4, 4, 4\\}"
-
+# When casting to vector the input type must have the same length as
+# the total length of the vector.
+gdb_test "print (char4) 0x01010101" "\\\$$decimal = \\{1, 1, 1, 1\\}"
+gdb_test "print (char4) ia" "\\\$$decimal = \\{2, 0, 0, 0\\}"
+gdb_test "print (int2) lla" "\\\$$decimal = \\{1, 1\\}"
+
+gdb_test "print (int2) 1" "can only cast scalar to vector of same size"
+gdb_test "print (longlong2) 2" "can only cast scalar to vector of same size"
+gdb_test "print (float2) 3" "can only cast scalar to vector of same size"
+gdb_test "print (double2) 4" "can only cast scalar to vector of same size"
+gdb_test "print (uint4) ia" "can only cast scalar to vector of same size"
+gdb_test "print (int4) -3" "can only cast scalar to vector of same size"
+gdb_test "print (float4) 4" "can only cast scalar to vector of same size"
+
+gdb_test "print i4b = ia" "can only cast scalar to vector of same size"
+gdb_test "print i4a = 3" "can only cast scalar to vector of same size"
+gdb_test "print f4a = fb" "can only cast scalar to vector of same size"
+gdb_test "print f4b = 2" "can only cast scalar to vector of same size"
+
+gdb_test "print c4 + lla" "conversion of scalar to vector involves truncation"
+gdb_test "print i4a + lla" "conversion of scalar to vector involves truncation"
+gdb_test "print lla + c4" "conversion of scalar to vector involves truncation"
+gdb_test "print lla + i4a" "conversion of scalar to vector involves truncation"
+
+gdb_test "print c4 + ib" "\\\$$decimal = \\{2, 3, 4, 5\\}"
 gdb_test "print i4a + ib" "\\\$$decimal = \\{3, 5, 9, 17\\}"
+gdb_test "print i4a + 1" "\\\$$decimal = \\{3, 5, 9, 17\\}"
+gdb_test "print 1 + i4a" "\\\$$decimal = \\{3, 5, 9, 17\\}"
 gdb_test "print fa - f4b" "\\\$$decimal = \\{1, 0, -6, -2\\}"
+gdb_test "print 2 - f4b" "\\\$$decimal = \\{1, 0, -6, -2\\}"
 gdb_test "print f4a * fb" "\\\$$decimal = \\{2, 4, 8, 16\\}"
+gdb_test "print f4a * 1" "\\\$$decimal = \\{2, 4, 8, 16\\}"
 gdb_test "print ia / i4b" "\\\$$decimal = \\{2, 1, 0, 0\\}"
+gdb_test "print 2 / i4b" "\\\$$decimal = \\{2, 1, 0, 0\\}"
 gdb_test "print i4a % ib" "\\\$$decimal = \\{0, 0, 0, 0\\}"
-
+gdb_test "print i4a % 1" "\\\$$decimal = \\{0, 0, 0, 0\\}"
 gdb_test "print ia & i4b" "\\\$$decimal = \\{0, 2, 0, 0\\}"
+gdb_test "print 2 & i4b" "\\\$$decimal = \\{0, 2, 0, 0\\}"
 gdb_test "print i4a | ib" "\\\$$decimal = \\{3, 5, 9, 17\\}"
+gdb_test "print i4a | 1" "\\\$$decimal = \\{3, 5, 9, 17\\}"
 gdb_test "print ia ^ i4b" "\\\$$decimal = \\{3, 0, 10, 6\\}"
+gdb_test "print 2 ^ i4b" "\\\$$decimal = \\{3, 0, 10, 6\\}"
 gdb_test "print i4a << ib" "\\\$$decimal = \\{4, 8, 16, 32\\}"
+gdb_test "print i4a << 1" "\\\$$decimal = \\{4, 8, 16, 32\\}"
 gdb_test "print i4a >> ib" "\\\$$decimal = \\{1, 2, 4, 8\\}"
-
-gdb_test "print i4b = ia" "\\\$$decimal = \\{2, 2, 2, 2\\}"
-gdb_test "print i4a = 3" "\\\$$decimal = \\{3, 3, 3, 3\\}"
-gdb_test "print f4a = fb" "\\\$$decimal = \\{1, 1, 1, 1\\}"
-gdb_test "print f4b = 2" "\\\$$decimal = \\{2, 2, 2, 2\\}"
+gdb_test "print i4a >> 1" "\\\$$decimal = \\{1, 2, 4, 8\\}"
 
 gdb_test "print i4a = \{2, 4, 8, 16\}" "\\\$$decimal = \\{2, 4, 8, 16\\}"
 gdb_test "print i4a <<= ib" "\\\$$decimal = \\{4, 8, 16, 32\\}"
@@ -130,6 +150,10 @@ gdb_test "print i2 + i4a" "Cannot perform operation on vectors with different ty
 gdb_test "print f4a + f2" "Cannot perform operation on vectors with different types"
 gdb_test "print f2 + f4a" "Cannot perform operation on vectors with different types"
 
+gdb_test "print (double2) f2" "Cannot convert between vector values of different sizes"
+gdb_test "print (int4) c4" "Cannot convert between vector values of different sizes"
+gdb_test "print (char4) i4a" "Cannot convert between vector values of different sizes"
+
 # Test ptype on vector types.
 gdb_test "ptype c4" "type = char __attribute__ \\(\\(vector_size\\(4\\)\\)\\)"
 gdb_test "ptype char4" "type = char __attribute__ \\(\\(vector_size\\(4\\)\\)\\)"