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riscv-gcc-1
Commit 65d8b1ce by Richard Kenner
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(fold, case BIT_IOR_EXPR): Recognize rotates with variable count. 

From-SVN: r11614
parent fda92428
Showing with 44 additions and 16 deletions
gcc/fold-const.c
...@@ -3901,6 +3901,9 @@ fold (expr) ...@@ -3901,6 +3901,9 @@ fold (expr)
case BIT_IOR_EXPR: case BIT_IOR_EXPR:
bit_ior: bit_ior:
{
register enum tree_code code0, code1;
if (integer_all_onesp (arg1)) if (integer_all_onesp (arg1))
return omit_one_operand (type, arg1, arg0); return omit_one_operand (type, arg1, arg0);
if (integer_zerop (arg1)) if (integer_zerop (arg1))
...@@ -3909,28 +3912,53 @@ fold (expr) ...@@ -3909,28 +3912,53 @@ fold (expr)
if (t1 != NULL_TREE) if (t1 != NULL_TREE)
return t1; return t1;
/* (a << C1) | (a >> C2) if A is unsigned and C1+C2 is the size of A /* (A << C1) | (A >> C2) if A is unsigned and C1+C2 is the size of A
is a rotate of A by C1 bits. */ is a rotate of A by C1 bits. */
/* (A << B) | (A >> (Z - B)) if A is unsigned and Z is the size of A
is a rotate of A by B bits. */
if ((TREE_CODE (arg0) == RSHIFT_EXPR code0 = TREE_CODE (arg0);
|| TREE_CODE (arg0) == LSHIFT_EXPR) code1 = TREE_CODE (arg1);
&& (TREE_CODE (arg1) == RSHIFT_EXPR if (((code0 == RSHIFT_EXPR && code1 == LSHIFT_EXPR)
|| TREE_CODE (arg1) == LSHIFT_EXPR) || (code1 == RSHIFT_EXPR && code0 == LSHIFT_EXPR))
&& TREE_CODE (arg0) != TREE_CODE (arg1)
&& operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1,0), 0) && operand_equal_p (TREE_OPERAND (arg0, 0), TREE_OPERAND (arg1,0), 0)
&& TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))) && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (arg0, 0))))
&& TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST {
&& TREE_CODE (TREE_OPERAND (arg1, 1)) == INTEGER_CST register tree tree01, tree11;
&& TREE_INT_CST_HIGH (TREE_OPERAND (arg0, 1)) == 0 register enum tree_code code01, code11;
&& TREE_INT_CST_HIGH (TREE_OPERAND (arg1, 1)) == 0
&& ((TREE_INT_CST_LOW (TREE_OPERAND (arg0, 1)) tree01 = TREE_OPERAND (arg0, 1);
+ TREE_INT_CST_LOW (TREE_OPERAND (arg1, 1))) tree11 = TREE_OPERAND (arg1, 1);
code01 = TREE_CODE (tree01);
code11 = TREE_CODE (tree11);
if (code01 == INTEGER_CST
&& code11 == INTEGER_CST
&& TREE_INT_CST_HIGH (tree01) == 0
&& TREE_INT_CST_HIGH (tree11) == 0
&& ((TREE_INT_CST_LOW (tree01) + TREE_INT_CST_LOW (tree11))
== TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0))))) == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))))
return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0), return build (LROTATE_EXPR, type, TREE_OPERAND (arg0, 0),
TREE_CODE (arg0) == LSHIFT_EXPR code0 == LSHIFT_EXPR ? tree01 : tree11);
? TREE_OPERAND (arg0, 1) : TREE_OPERAND (arg1, 1)); else if (code11 == MINUS_EXPR
&& TREE_CODE (TREE_OPERAND (tree11, 0)) == INTEGER_CST
&& TREE_INT_CST_HIGH (TREE_OPERAND (tree11, 0)) == 0
&& TREE_INT_CST_LOW (TREE_OPERAND (tree11, 0))
== TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))
&& operand_equal_p (tree01, TREE_OPERAND (tree11, 1), 0))
return build (code0 == LSHIFT_EXPR ? LROTATE_EXPR : RROTATE_EXPR,
type, TREE_OPERAND (arg0, 0), tree01);
else if (code01 == MINUS_EXPR
&& TREE_CODE (TREE_OPERAND (tree01, 0)) == INTEGER_CST
&& TREE_INT_CST_HIGH (TREE_OPERAND (tree01, 0)) == 0
&& TREE_INT_CST_LOW (TREE_OPERAND (tree01, 0))
== TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (arg0, 0)))
&& operand_equal_p (tree11, TREE_OPERAND (tree01, 1), 0))
return build (code0 != LSHIFT_EXPR ? LROTATE_EXPR : RROTATE_EXPR,
type, TREE_OPERAND (arg0, 0), tree11);
}
goto associate; goto associate;
}
case BIT_XOR_EXPR: case BIT_XOR_EXPR:
if (integer_zerop (arg1)) if (integer_zerop (arg1))
......
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