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Re: [PATCH] Fix PR49715, (float)unsigned -> (float)signed
On Fri, 22 Jul 2011, Richard Guenther wrote:
> On Thu, 21 Jul 2011, Joseph S. Myers wrote:
>
> > On Thu, 21 Jul 2011, Richard Guenther wrote:
> >
> > > Patch also handling wider modes and not starting with SImode but
> > > the mode of int:
> >
> > Use of target int for anything not about C ABIs is certainly wrong. This
> > might be about what operations the target does efficiently, or what
> > functions are present in libgcc (both of which would be functions of
> > machine modes), but it's not about the choice of C int.
>
> Ok. Given rths last suggestion I'm testing the following which
> checks all integer modes (but never will widen - optabs.c will do
> that if it turns out to be profitable).
Err, I should refresh the patch before sending it ... here it goes.
Richard.
2011-07-22 Richard Guenther <rguenther@suse.de>
PR tree-optimization/49715
* tree-vrp.c: Include expr.h and optabs.h.
(simplify_float_conversion_using_ranges): New function.
(simplify_stmt_using_ranges): Call it.
* Makefile.in (tree-vrp.o): Add $(EXPR_H) and $(OPTABS_H) dependencies.
* optabs.c (can_float_p): Export.
* optabs.h (can_float_p): Declare.
* gcc.target/i386/pr49715-1.c: New testcase.
* gcc.target/i386/pr49715-2.c: Likewise.
Index: gcc/tree-vrp.c
===================================================================
*** gcc/tree-vrp.c.orig 2011-07-21 17:46:16.000000000 +0200
--- gcc/tree-vrp.c 2011-07-22 11:09:03.000000000 +0200
*************** along with GCC; see the file COPYING3.
*** 40,45 ****
--- 40,47 ----
#include "tree-ssa-propagate.h"
#include "tree-chrec.h"
#include "gimple-fold.h"
+ #include "expr.h"
+ #include "optabs.h"
/* Type of value ranges. See value_range_d for a description of these
*************** simplify_conversion_using_ranges (gimple
*** 7448,7453 ****
--- 7450,7520 ----
return true;
}
+ /* Simplify a conversion from integral SSA name to float in STMT. */
+
+ static bool
+ simplify_float_conversion_using_ranges (gimple_stmt_iterator *gsi, gimple stmt)
+ {
+ tree rhs1 = gimple_assign_rhs1 (stmt);
+ value_range_t *vr = get_value_range (rhs1);
+ enum machine_mode fltmode = TYPE_MODE (TREE_TYPE (gimple_assign_lhs (stmt)));
+ enum machine_mode mode;
+ tree tem;
+ gimple conv;
+
+ /* We can only handle constant ranges. */
+ if (vr->type != VR_RANGE
+ || TREE_CODE (vr->min) != INTEGER_CST
+ || TREE_CODE (vr->max) != INTEGER_CST)
+ return false;
+
+ /* Search for a mode we can use. */
+ mode = GET_CLASS_NARROWEST_MODE (MODE_INT);
+ do
+ {
+ double_int tem;
+
+ /* If we cannot do a signed conversion to float from mode
+ or if the value-range does not fit in the signed type
+ try with a wider mode. */
+ if (can_float_p (fltmode, mode, 0) != CODE_FOR_nothing)
+ {
+ tem = double_int_ext (tree_to_double_int (vr->min),
+ GET_MODE_PRECISION (mode), 0);
+ if (double_int_equal_p (tree_to_double_int (vr->min), tem))
+ {
+ tem = double_int_ext (tree_to_double_int (vr->max),
+ GET_MODE_PRECISION (mode), 0);
+ if (double_int_equal_p (tree_to_double_int (vr->max), tem))
+ break;
+ }
+ }
+
+ mode = GET_MODE_WIDER_MODE (mode);
+ /* But do not widen the input. Instead leave that to the
+ optabs expansion code. */
+ if (GET_MODE_PRECISION (mode) > TYPE_PRECISION (TREE_TYPE (rhs1)))
+ return false;
+ }
+ while (mode != VOIDmode);
+
+ if (mode == VOIDmode)
+ return false;
+
+ /* It works, insert a truncation or sign-change before the
+ float conversion. */
+ tem = create_tmp_var (build_nonstandard_integer_type
+ (GET_MODE_PRECISION (mode), 0), NULL);
+ conv = gimple_build_assign_with_ops (NOP_EXPR, tem, rhs1, NULL_TREE);
+ tem = make_ssa_name (tem, conv);
+ gimple_assign_set_lhs (conv, tem);
+ gsi_insert_before (gsi, conv, GSI_SAME_STMT);
+ gimple_assign_set_rhs1 (stmt, tem);
+ update_stmt (stmt);
+
+ return true;
+ }
+
/* Simplify STMT using ranges if possible. */
static bool
*************** simplify_stmt_using_ranges (gimple_stmt_
*** 7507,7512 ****
--- 7574,7585 ----
return simplify_conversion_using_ranges (stmt);
break;
+ case FLOAT_EXPR:
+ if (TREE_CODE (rhs1) == SSA_NAME
+ && INTEGRAL_TYPE_P (TREE_TYPE (rhs1)))
+ return simplify_float_conversion_using_ranges (gsi, stmt);
+ break;
+
default:
break;
}
Index: gcc/testsuite/gcc.target/i386/pr49715-1.c
===================================================================
*** /dev/null 1970-01-01 00:00:00.000000000 +0000
--- gcc/testsuite/gcc.target/i386/pr49715-1.c 2011-07-21 17:46:39.000000000 +0200
***************
*** 0 ****
--- 1,9 ----
+ /* { dg-do compile } */
+ /* { dg-options "-O2 -msse -mfpmath=sse" } */
+
+ float func(unsigned x)
+ {
+ return (x & 0xfffff) * 0.01f;
+ }
+
+ /* { dg-final { scan-assembler-times "cvtsi2ss" 1 } } */
Index: gcc/testsuite/gcc.target/i386/pr49715-2.c
===================================================================
*** /dev/null 1970-01-01 00:00:00.000000000 +0000
--- gcc/testsuite/gcc.target/i386/pr49715-2.c 2011-07-21 17:46:39.000000000 +0200
***************
*** 0 ****
--- 1,12 ----
+ /* { dg-do compile } */
+ /* { dg-require-effective-target lp64 } */
+ /* { dg-options "-O2" } */
+
+ double func(unsigned long long x)
+ {
+ if (x <= 0x7ffffffffffffffeULL)
+ return (x + 1) * 0.01;
+ return 0.0;
+ }
+
+ /* { dg-final { scan-assembler-times "cvtsi2sdq" 1 } } */
Index: gcc/Makefile.in
===================================================================
*** gcc/Makefile.in.orig 2011-07-19 12:59:09.000000000 +0200
--- gcc/Makefile.in 2011-07-22 11:09:16.000000000 +0200
*************** tree-vrp.o : tree-vrp.c $(CONFIG_H) $(SY
*** 2504,2510 ****
$(TREE_FLOW_H) $(TREE_PASS_H) $(TREE_DUMP_H) $(DIAGNOSTIC_H) $(GGC_H) \
$(BASIC_BLOCK_H) tree-ssa-propagate.h $(FLAGS_H) $(TREE_DUMP_H) \
$(CFGLOOP_H) $(SCEV_H) $(TIMEVAR_H) intl.h tree-pretty-print.h \
! gimple-pretty-print.h gimple-fold.h
tree-cfg.o : tree-cfg.c $(TREE_FLOW_H) $(CONFIG_H) $(SYSTEM_H) \
$(TREE_H) $(TM_P_H) $(EXPR_H) $(GGC_H) $(FLAGS_H) output.h \
$(DIAGNOSTIC_H) $(FUNCTION_H) $(TIMEVAR_H) $(TM_H) coretypes.h \
--- 2504,2510 ----
$(TREE_FLOW_H) $(TREE_PASS_H) $(TREE_DUMP_H) $(DIAGNOSTIC_H) $(GGC_H) \
$(BASIC_BLOCK_H) tree-ssa-propagate.h $(FLAGS_H) $(TREE_DUMP_H) \
$(CFGLOOP_H) $(SCEV_H) $(TIMEVAR_H) intl.h tree-pretty-print.h \
! gimple-pretty-print.h gimple-fold.h $(OPTABS_H) $(EXPR_H)
tree-cfg.o : tree-cfg.c $(TREE_FLOW_H) $(CONFIG_H) $(SYSTEM_H) \
$(TREE_H) $(TM_P_H) $(EXPR_H) $(GGC_H) $(FLAGS_H) output.h \
$(DIAGNOSTIC_H) $(FUNCTION_H) $(TIMEVAR_H) $(TM_H) coretypes.h \
Index: gcc/optabs.c
===================================================================
*** gcc/optabs.c.orig 2011-07-11 17:02:51.000000000 +0200
--- gcc/optabs.c 2011-07-22 11:04:42.000000000 +0200
*************** can_fix_p (enum machine_mode fixmode, en
*** 4626,4632 ****
return CODE_FOR_nothing;
}
! static enum insn_code
can_float_p (enum machine_mode fltmode, enum machine_mode fixmode,
int unsignedp)
{
--- 4626,4632 ----
return CODE_FOR_nothing;
}
! enum insn_code
can_float_p (enum machine_mode fltmode, enum machine_mode fixmode,
int unsignedp)
{
Index: gcc/optabs.h
===================================================================
*** gcc/optabs.h.orig 2011-06-22 16:01:28.000000000 +0200
--- gcc/optabs.h 2011-07-22 11:06:01.000000000 +0200
*************** extern void expand_fixed_convert (rtx, r
*** 849,854 ****
--- 849,857 ----
/* Generate code for a FLOAT_EXPR. */
extern void expand_float (rtx, rtx, int);
+ /* Return the insn_code for a FLOAT_EXPR. */
+ enum insn_code can_float_p (enum machine_mode, enum machine_mode, int);
+
/* Generate code for a FIX_EXPR. */
extern void expand_fix (rtx, rtx, int);