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| author | Roger Sayle <roger@eyesopen.com> | 2004-07-01 13:09:39 +0000 |
|---|---|---|
| committer | Roger Sayle <sayle@gcc.gnu.org> | 2004-07-01 13:09:39 +0000 |
| commit | aec53add6aee0e7461c65a2893f17c8fdf8a3615 (patch) | |
| tree | 7d647f707e994c9eeea5a4841a73dd0d482ff1c3 | |
| parent | 3c0cb5de6a4e067a36096c2141384bf9e3f520b6 (diff) | |
| download | gcc-aec53add6aee0e7461c65a2893f17c8fdf8a3615.zip gcc-aec53add6aee0e7461c65a2893f17c8fdf8a3615.tar.gz gcc-aec53add6aee0e7461c65a2893f17c8fdf8a3615.tar.bz2 | |
simplify-rtx.c (simplify_binary_operation): Use rtx_cost instead of "had_mult" to determine whether the transformed...
* simplify-rtx.c (simplify_binary_operation) <PLUS, MINUS>: Use
rtx_cost instead of "had_mult" to determine whether the transformed
expression is cheaper than the original.
From-SVN: r83981
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/simplify-rtx.c | 20 |
2 files changed, 15 insertions, 11 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 6e00281..6970465 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2004-07-01 Roger Sayle <roger@eyesopen.com> + + * simplify-rtx.c (simplify_binary_operation) <PLUS, MINUS>: Use + rtx_cost instead of "had_mult" to determine whether the transformed + expression is cheaper than the original. + 2004-07-01 Jerry Quinn <jlquinn@optonline.net> * alias.c (get_alias_set, canon_rtx, get_addr, diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index 0d24be8..3789f33 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -1506,13 +1506,12 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, if the multiplication is written as a shift. If so, we can distribute and make a new multiply, shift, or maybe just have X (if C is 2 in the example above). But don't make - real multiply if we didn't have one before. */ + something more expensive than we had before. */ if (! FLOAT_MODE_P (mode)) { HOST_WIDE_INT coeff0 = 1, coeff1 = 1; rtx lhs = op0, rhs = op1; - int had_mult = 0; if (GET_CODE (lhs) == NEG) coeff0 = -1, lhs = XEXP (lhs, 0); @@ -1520,7 +1519,6 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, && GET_CODE (XEXP (lhs, 1)) == CONST_INT) { coeff0 = INTVAL (XEXP (lhs, 1)), lhs = XEXP (lhs, 0); - had_mult = 1; } else if (GET_CODE (lhs) == ASHIFT && GET_CODE (XEXP (lhs, 1)) == CONST_INT @@ -1537,7 +1535,6 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, && GET_CODE (XEXP (rhs, 1)) == CONST_INT) { coeff1 = INTVAL (XEXP (rhs, 1)), rhs = XEXP (rhs, 0); - had_mult = 1; } else if (GET_CODE (rhs) == ASHIFT && GET_CODE (XEXP (rhs, 1)) == CONST_INT @@ -1550,9 +1547,11 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, if (rtx_equal_p (lhs, rhs)) { + rtx orig = gen_rtx_PLUS (mode, op0, op1); tem = simplify_gen_binary (MULT, mode, lhs, - GEN_INT (coeff0 + coeff1)); - return (GET_CODE (tem) == MULT && ! had_mult) ? 0 : tem; + GEN_INT (coeff0 + coeff1)); + return rtx_cost (tem, SET) <= rtx_cost (orig, SET) + ? tem : 0; } } @@ -1661,13 +1660,12 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, if the multiplication is written as a shift. If so, we can distribute and make a new multiply, shift, or maybe just have X (if C is 2 in the example above). But don't make - real multiply if we didn't have one before. */ + something more expensive than we had before. */ if (! FLOAT_MODE_P (mode)) { HOST_WIDE_INT coeff0 = 1, coeff1 = 1; rtx lhs = op0, rhs = op1; - int had_mult = 0; if (GET_CODE (lhs) == NEG) coeff0 = -1, lhs = XEXP (lhs, 0); @@ -1675,7 +1673,6 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, && GET_CODE (XEXP (lhs, 1)) == CONST_INT) { coeff0 = INTVAL (XEXP (lhs, 1)), lhs = XEXP (lhs, 0); - had_mult = 1; } else if (GET_CODE (lhs) == ASHIFT && GET_CODE (XEXP (lhs, 1)) == CONST_INT @@ -1692,7 +1689,6 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, && GET_CODE (XEXP (rhs, 1)) == CONST_INT) { coeff1 = INTVAL (XEXP (rhs, 1)), rhs = XEXP (rhs, 0); - had_mult = 1; } else if (GET_CODE (rhs) == ASHIFT && GET_CODE (XEXP (rhs, 1)) == CONST_INT @@ -1705,9 +1701,11 @@ simplify_binary_operation (enum rtx_code code, enum machine_mode mode, if (rtx_equal_p (lhs, rhs)) { + rtx orig = gen_rtx_MINUS (mode, op0, op1); tem = simplify_gen_binary (MULT, mode, lhs, GEN_INT (coeff0 - coeff1)); - return (GET_CODE (tem) == MULT && ! had_mult) ? 0 : tem; + return rtx_cost (tem, SET) <= rtx_cost (orig, SET) + ? tem : 0; } } |