From d3b726902460a92cefbb1be7472d2cafece201ed Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Tue, 28 Feb 2006 20:32:20 +0000 Subject: rtl.h (truncated_to_mode): Declare it. * rtl.h (truncated_to_mode): Declare it. (struct rtl_hooks): Add reg_truncated_to_mode hook. * rtlhooks-def.h (RTL_HOOKS_REG_TRUNCATED_TO_MODE): New macro. (RTL_HOOKS_INITIALIZER): Include it. * rtlhooks.c (reg_truncated_to_mode_general): New function. * combine.c (RTL_HOOKS_REG_TRUNCATED_TO_MODE): Override to reg_truncated_to_mode. * rtlanal.c (truncated_to_mode): Define it. * simplify-rtx.c (simplify_unary_operation_1): Use it. Co-Authored-By: Adam Nemet From-SVN: r111573 --- gcc/ChangeLog | 13 +++++++++++++ gcc/combine.c | 3 +++ gcc/rtl.h | 4 +++- gcc/rtlanal.c | 10 ++++++++++ gcc/rtlhooks-def.h | 3 +++ gcc/rtlhooks.c | 7 +++++++ gcc/simplify-rtx.c | 17 ++++++++++------- 7 files changed, 49 insertions(+), 8 deletions(-) (limited to 'gcc') diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 7ba3134..d37067c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,16 @@ +2006-02-28 Paolo Bonzini + Adam Nemet + + * rtl.h (truncated_to_mode): Declare it. + (struct rtl_hooks): Add reg_truncated_to_mode hook. + * rtlhooks-def.h (RTL_HOOKS_REG_TRUNCATED_TO_MODE): New macro. + (RTL_HOOKS_INITIALIZER): Include it. + * rtlhooks.c (reg_truncated_to_mode_general): New function. + * combine.c (RTL_HOOKS_REG_TRUNCATED_TO_MODE): Override to + reg_truncated_to_mode. + * rtlanal.c (truncated_to_mode): Define it. + * simplify-rtx.c (simplify_unary_operation_1): Use it. + 2006-02-28 Jeff Law * tree-chrec.c (chrec_convert_aggressive): Do not eliminate diff --git a/gcc/combine.c b/gcc/combine.c index 443b429..32d3f67 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -457,6 +457,9 @@ static rtx gen_lowpart_or_truncate (enum machine_mode, rtx); #undef RTL_HOOKS_REG_NUM_SIGN_BIT_COPIES #define RTL_HOOKS_REG_NUM_SIGN_BIT_COPIES reg_num_sign_bit_copies_for_combine +#undef RTL_HOOKS_REG_TRUNCATED_TO_MODE +#define RTL_HOOKS_REG_TRUNCATED_TO_MODE reg_truncated_to_mode + static const struct rtl_hooks combine_rtl_hooks = RTL_HOOKS_INITIALIZER; diff --git a/gcc/rtl.h b/gcc/rtl.h index 6e17a22..9c088e9 100644 --- a/gcc/rtl.h +++ b/gcc/rtl.h @@ -1047,6 +1047,7 @@ extern unsigned int subreg_regno (rtx); extern unsigned HOST_WIDE_INT nonzero_bits (rtx, enum machine_mode); extern unsigned int num_sign_bit_copies (rtx, enum machine_mode); extern bool constant_pool_constant_p (rtx); +extern bool truncated_to_mode (enum machine_mode, rtx); /* 1 if RTX is a subreg containing a reg that is already known to be @@ -2277,8 +2278,9 @@ struct rtl_hooks unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT *); rtx (*reg_num_sign_bit_copies) (rtx, enum machine_mode, rtx, enum machine_mode, unsigned int, unsigned int *); + bool (*reg_truncated_to_mode) (enum machine_mode, rtx); - /* Whenever you add entries here, make sure you adjust hosthooks-def.h. */ + /* Whenever you add entries here, make sure you adjust rtlhooks-def.h. */ }; /* Each pass can provide its own. */ diff --git a/gcc/rtlanal.c b/gcc/rtlanal.c index d8c9fb8..bbf7e71 100644 --- a/gcc/rtlanal.c +++ b/gcc/rtlanal.c @@ -4808,6 +4808,16 @@ get_condition (rtx jump, rtx *earliest, int allow_cc_mode, int valid_at_insn_p) allow_cc_mode, valid_at_insn_p); } +/* Suppose that truncation from the machine mode of X to MODE is not a + no-op. See if there is anything special about X so that we can + assume it already contains a truncated value of MODE. */ + +bool +truncated_to_mode (enum machine_mode mode, rtx x) +{ + return REG_P (x) && rtl_hooks.reg_truncated_to_mode (mode, x); +} + /* Initialize non_rtx_starting_operands, which is used to speed up for_each_rtx. */ diff --git a/gcc/rtlhooks-def.h b/gcc/rtlhooks-def.h index b6c07fb..748666c 100644 --- a/gcc/rtlhooks-def.h +++ b/gcc/rtlhooks-def.h @@ -27,6 +27,7 @@ Boston, MA 02110-1301, USA. */ #define RTL_HOOKS_GEN_LOWPART_NO_EMIT gen_lowpart_no_emit_general #define RTL_HOOKS_REG_NONZERO_REG_BITS reg_nonzero_bits_general #define RTL_HOOKS_REG_NUM_SIGN_BIT_COPIES reg_num_sign_bit_copies_general +#define RTL_HOOKS_REG_TRUNCATED_TO_MODE reg_truncated_to_mode_general /* The structure is defined in rtl.h. */ #define RTL_HOOKS_INITIALIZER { \ @@ -34,6 +35,7 @@ Boston, MA 02110-1301, USA. */ RTL_HOOKS_GEN_LOWPART_NO_EMIT, \ RTL_HOOKS_REG_NONZERO_REG_BITS, \ RTL_HOOKS_REG_NUM_SIGN_BIT_COPIES, \ + RTL_HOOKS_REG_TRUNCATED_TO_MODE, \ } extern rtx gen_lowpart_general (enum machine_mode, rtx); @@ -45,5 +47,6 @@ extern rtx reg_nonzero_bits_general (rtx, enum machine_mode, rtx, extern rtx reg_num_sign_bit_copies_general (rtx, enum machine_mode, rtx, enum machine_mode, unsigned int, unsigned int *); +extern bool reg_truncated_to_mode_general (enum machine_mode, rtx); #endif /* GCC_RTL_HOOKS_DEF_H */ diff --git a/gcc/rtlhooks.c b/gcc/rtlhooks.c index 0034da7..ece7198 100644 --- a/gcc/rtlhooks.c +++ b/gcc/rtlhooks.c @@ -117,6 +117,13 @@ reg_nonzero_bits_general (rtx x ATTRIBUTE_UNUSED, return NULL; } +bool +reg_truncated_to_mode_general (enum machine_mode mode ATTRIBUTE_UNUSED, + rtx x ATTRIBUTE_UNUSED) +{ + return false; +} + /* Assuming that X is an rtx (e.g., MEM, REG or SUBREG) for a fixed-point number, return an rtx (MEM, SUBREG, or CONST_INT) that refers to the least-significant part of X. diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index e84beda..aded68e 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -631,14 +631,17 @@ simplify_unary_operation_1 (enum rtx_code code, enum machine_mode mode, rtx op) GET_MODE (XEXP (SUBREG_REG (op), 0))); /* If we know that the value is already truncated, we can - replace the TRUNCATE with a SUBREG if TRULY_NOOP_TRUNCATION - is nonzero for the corresponding modes. But don't do this - for an (LSHIFTRT (MULT ...)) since this will cause problems - with the umulXi3_highpart patterns. */ - if (TRULY_NOOP_TRUNCATION (GET_MODE_BITSIZE (mode), + replace the TRUNCATE with a SUBREG. Note that this is also + valid if TRULY_NOOP_TRUNCATION is false for the corresponding + modes we just have to apply a different definition for + truncation. But don't do this for an (LSHIFTRT (MULT ...)) + since this will cause problems with the umulXi3_highpart + patterns. */ + if ((TRULY_NOOP_TRUNCATION (GET_MODE_BITSIZE (mode), GET_MODE_BITSIZE (GET_MODE (op))) - && num_sign_bit_copies (op, GET_MODE (op)) - >= (unsigned int) (GET_MODE_BITSIZE (mode) + 1) + ? (num_sign_bit_copies (op, GET_MODE (op)) + >= (unsigned int) (GET_MODE_BITSIZE (mode) + 1)) + : truncated_to_mode (mode, op)) && ! (GET_CODE (op) == LSHIFTRT && GET_CODE (XEXP (op, 0)) == MULT)) return rtl_hooks.gen_lowpart_no_emit (mode, op); -- cgit v1.1