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| author | Ian Lance Taylor <ian@gcc.gnu.org> | 1997-01-23 20:05:52 +0000 |
|---|---|---|
| committer | Ian Lance Taylor <ian@gcc.gnu.org> | 1997-01-23 20:05:52 +0000 |
| commit | 38734e55b348c29115121efadb90275d3f150e81 (patch) | |
| tree | 0b69b9ae0996ddabd4c7781e7103fbac1a0d0deb /gcc | |
| parent | 26bbb20697bc7ad7df8903005843dea21ee3b7fc (diff) | |
| download | gcc-38734e55b348c29115121efadb90275d3f150e81.zip gcc-38734e55b348c29115121efadb90275d3f150e81.tar.gz gcc-38734e55b348c29115121efadb90275d3f150e81.tar.bz2 | |
Get the right COST for a SUBREG when truncating
From-SVN: r13549
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/cse.c | 26 |
1 files changed, 19 insertions, 7 deletions
@@ -1,5 +1,5 @@ /* Common subexpression elimination for GNU compiler. - Copyright (C) 1987, 88, 89, 92-5, 1996 Free Software Foundation, Inc. + Copyright (C) 1987, 88, 89, 92-6, 1997 Free Software Foundation, Inc. This file is part of GNU CC. @@ -478,12 +478,24 @@ struct table_elt ((REG_USERVAR_P (N) && REGNO (N) < FIRST_PSEUDO_REGISTER) \ || CHEAP_REGNO (REGNO (N))) -#define COST(X) \ - (GET_CODE (X) == REG \ - ? (CHEAP_REG (X) ? 0 \ - : REGNO (X) >= FIRST_PSEUDO_REGISTER ? 1 \ - : 2) \ - : rtx_cost (X, SET) * 2) +#define COST(X) \ + (GET_CODE (X) == REG \ + ? (CHEAP_REG (X) ? 0 \ + : REGNO (X) >= FIRST_PSEUDO_REGISTER ? 1 \ + : 2) \ + : ((GET_CODE (X) == SUBREG \ + && GET_CODE (SUBREG_REG (X)) == REG \ + && GET_MODE_CLASS (GET_MODE (X)) == MODE_INT \ + && GET_MODE_CLASS (GET_MODE (SUBREG_REG (X))) == MODE_INT \ + && (GET_MODE_SIZE (GET_MODE (X)) \ + < GET_MODE_SIZE (GET_MODE (SUBREG_REG (X)))) \ + && subreg_lowpart_p (X) \ + && TRULY_NOOP_TRUNCATION (GET_MODE_BITSIZE (GET_MODE (X)), \ + GET_MODE_BITSIZE (GET_MODE (SUBREG_REG (X))))) \ + ? (CHEAP_REG (SUBREG_REG (X)) ? 0 \ + : REGNO (SUBREG_REG (X)) >= FIRST_PSEUDO_REGISTER ? 1 \ + : 2) \ + : rtx_cost (X, SET) * 2)) /* Determine if the quantity number for register X represents a valid index into the `qty_...' variables. */ |