From 5ee5a056ed23a62c4b02c6b74f9c4b4abda5de57 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 23 Jan 2004 12:42:48 -0800 Subject: [PATCH] combine.c (SHIFT_COUNT_TRUNCATED): Provide default value. * combine.c (SHIFT_COUNT_TRUNCATED): Provide default value. (simplify_comparison): Don't simplify (eq (zero_extract c 1 r) 0) if SHIFT_COUNT_TRUNCATED is set. From-SVN: r76451 --- gcc/ChangeLog | 7 +++++++ gcc/combine.c | 15 ++++++++------- 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 27bdc0d957a4..972c509e9525 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2004-01-23 Richard Henderson + + PR opt/12941 + * combine.c (SHIFT_COUNT_TRUNCATED): Provide default value. + (simplify_comparison): Don't simplify (eq (zero_extract c 1 r) 0) + if SHIFT_COUNT_TRUNCATED is set. + 2004-01-23 Ian Lance Taylor * doc/invoke.texi (Optimize Options): Note that --param arguments diff --git a/gcc/combine.c b/gcc/combine.c index 7b0e6a6f8063..b26053c5ad2a 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -87,6 +87,10 @@ Software Foundation, 59 Temple Place - Suite 330, Boston, MA #include "real.h" #include "toplev.h" +#ifndef SHIFT_COUNT_TRUNCATED +#define SHIFT_COUNT_TRUNCATED 0 +#endif + /* It is not safe to use ordinary gen_lowpart in combine. Use gen_lowpart_for_combine instead. See comments there. */ #define gen_lowpart dont_use_gen_lowpart_you_dummy @@ -4691,7 +4695,6 @@ combine_simplify_rtx (x, op0_mode, last, in_dest) return simplify_shift_const (x, code, mode, XEXP (x, 0), INTVAL (XEXP (x, 1))); -#ifdef SHIFT_COUNT_TRUNCATED else if (SHIFT_COUNT_TRUNCATED && GET_CODE (XEXP (x, 1)) != REG) SUBST (XEXP (x, 1), force_to_mode (XEXP (x, 1), GET_MODE (XEXP (x, 1)), @@ -4699,8 +4702,6 @@ combine_simplify_rtx (x, op0_mode, last, in_dest) << exact_log2 (GET_MODE_BITSIZE (GET_MODE (x)))) - 1, NULL_RTX, 0)); -#endif - break; case VEC_SELECT: @@ -9271,10 +9272,8 @@ simplify_shift_const (x, code, result_mode, varop, orig_count) /* Make sure and truncate the "natural" shift on the way in. We don't want to do this inside the loop as it makes it more difficult to combine shifts. */ -#ifdef SHIFT_COUNT_TRUNCATED if (SHIFT_COUNT_TRUNCATED) orig_count &= GET_MODE_BITSIZE (mode) - 1; -#endif /* If we were given an invalid count, don't do anything except exactly what was requested. */ @@ -10664,8 +10663,10 @@ simplify_comparison (code, pop0, pop1) a constant that has only a single bit set and are comparing it with zero, we can convert this into an equality comparison between the position and the location of the single bit. */ - - if (GET_CODE (XEXP (op0, 0)) == CONST_INT + /* Except we can't if SHIFT_COUNT_TRUNCATED is set, since we might + have already reduced the shift count modulo the word size. */ + if (!SHIFT_COUNT_TRUNCATED + && GET_CODE (XEXP (op0, 0)) == CONST_INT && XEXP (op0, 1) == const1_rtx && equality_comparison_p && const_op == 0 && (i = exact_log2 (INTVAL (XEXP (op0, 0)))) >= 0) -- 2.47.2