<result> = shr <ty> <var1>, ubyte <var2> ; yields {ty}:result
+ <result> = lshr <ty> <var1>, ubyte <var2> ; yields {ty}:result
+
Overview:
-The 'shr' instruction returns the first operand shifted to
-the right a specified number of bits.
+The 'lshr' instruction (logical shift right) returns the first
+operand shifted to the right a specified number of bits.
+
Arguments:
-The first argument to the 'shr' instruction must be an integer type. The second argument must be an 'ubyte'
-type.
+The first argument to the 'lshr' instruction must be an integer type. The second argument must be an 'ubyte' type.
+
Semantics:
-If the first argument is a signed type, the
-most significant bit is duplicated in the newly free'd bit positions.
-If the first argument is unsigned, zero bits shall fill the empty
-positions.
+This instruction always performs a logical shift right operation, regardless
+of whether the arguments are unsigned or not. The var2 most significant
+bits will be filled with zero bits after the shift.
+
Example:
- <result> = shr int 4, ubyte %var ; yields {int}:result = 4 >> %var
- <result> = shr uint 4, ubyte 1 ; yields {uint}:result = 2
- <result> = shr int 4, ubyte 2 ; yields {int}:result = 1
- <result> = shr sbyte 4, ubyte 3 ; yields {sbyte}:result = 0
- <result> = shr sbyte -2, ubyte 1 ; yields {sbyte}:result = -1
+
+ <result> = lshr uint 4, ubyte 1 ; yields {uint}:result = 2
+ <result> = lshr int 4, ubyte 2 ; yields {uint}:result = 1
+ <result> = lshr sbyte 4, ubyte 3 ; yields {sbyte}:result = 0
+ <result> = lshr sbyte -2, ubyte 1 ; yields {sbyte}:result = 0x7FFFFFFF
+
+ <result> = ashr <ty> <var1>, ubyte <var2> ; yields {ty}:result
+
+
+The 'ashr' instruction (arithmetic shift right) returns the first +operand shifted to the right a specified number of bits.
+ +The first argument to the 'ashr' instruction must be an +integer type. The second argument must be an +'ubyte' type.
+ +This instruction always performs an arithmetic shift right operation, +regardless of whether the arguments are signed or not. The var2 most +significant bits will be filled with the sign bit of var1.
+ +
+ <result> = ashr uint 4, ubyte 1 ; yields {uint}:result = 2
+ <result> = ashr int 4, ubyte 2 ; yields {int}:result = 1
+ <result> = ashr ubyte 4, ubyte 3 ; yields {ubyte}:result = 0
+ <result> = ashr sbyte -2, ubyte 1 ; yields {sbyte}:result = -1