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| author | Jan Hubicka <jh@suse.cz> | 2000-04-23 20:25:40 +0000 |
|---|---|---|
| committer | Jan Hubicka <hubicka@gcc.gnu.org> | 2000-04-23 20:25:40 +0000 |
| commit | 29aef5ca814ab84976d233755a0e8d442fe47232 (patch) | |
| tree | d43104339ec7984ca3c0a48c418e6b90d6f87ddc /gcc | |
| parent | ff2b942e78dc46a8705f54ccd352c51b61163829 (diff) | |
| download | gcc-29aef5ca814ab84976d233755a0e8d442fe47232.zip gcc-29aef5ca814ab84976d233755a0e8d442fe47232.tar.gz gcc-29aef5ca814ab84976d233755a0e8d442fe47232.tar.bz2 | |
loop.c (simplify_giv_expr): Be more agressive on simplifying constant MULT givs.
* loop.c (simplify_giv_expr): Be more agressive on simplifying
constant MULT givs.
From-SVN: r33357
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/loop.c | 41 |
2 files changed, 33 insertions, 13 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 6351846..6456636 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +Sun Apr 23 22:23:08 MET DST 2000 Jan Hubicka <jh@suse.cz> + + * loop.c (simplify_giv_expr): Be more agressive on simplifying + constant MULT givs. + 2000-04-23 Zack Weinberg <zack@wolery.cumb.org> * cpphash.h (struct definition): Move file, line, col members... @@ -6402,25 +6402,40 @@ simplify_giv_expr (loop, x, benefit) return GEN_INT (INTVAL (arg0) * INTVAL (arg1)); case USE: - /* invar * invar. It is a giv, but very few of these will - actually pay off, so limit to simple registers. */ + /* invar * invar is a giv, but attempt to simplify it somehow. */ if (GET_CODE (arg1) != CONST_INT) return NULL_RTX; arg0 = XEXP (arg0, 0); - if (GET_CODE (arg0) == REG) - tem = gen_rtx_MULT (mode, arg0, arg1); - else if (GET_CODE (arg0) == MULT - && GET_CODE (XEXP (arg0, 0)) == REG - && GET_CODE (XEXP (arg0, 1)) == CONST_INT) + if (GET_CODE (arg0) == MULT) { - tem = gen_rtx_MULT (mode, XEXP (arg0, 0), - GEN_INT (INTVAL (XEXP (arg0, 1)) - * INTVAL (arg1))); + /* (invar_0 * invar_1) * invar_2. Associate. */ + return simplify_giv_expr (loop, + gen_rtx_MULT (mode, + XEXP (arg0, 0), + gen_rtx_MULT (mode, + XEXP (arg0, + 1), + arg1)), + benefit); } - else - return NULL_RTX; - return gen_rtx_USE (mode, tem); + /* Porpagate the MULT expressions to the intermost nodes. */ + else if (GET_CODE (arg0) == PLUS) + { + /* (invar_0 + invar_1) * invar_2. Distribute. */ + return simplify_giv_expr (loop, + gen_rtx_PLUS (mode, + gen_rtx_MULT (mode, + XEXP (arg0, + 0), + arg1), + gen_rtx_MULT (mode, + XEXP (arg0, + 1), + arg1)), + benefit); + } + return gen_rtx_USE (mode, gen_rtx_MULT (mode, arg0, arg1)); case MULT: /* (a * invar_1) * invar_2. Associate. */ |