This patch makes more use of the existing paradoxical_subreg_p
predicate and also adds a version that operates on outer and
inner modes.
Some of the affected tests were based on GET_MODE_SIZE rather than
GET_MODE_PRECISION and so the patch could change the result for modes
that have the same size but different precisions. I think in each
case the change should be a no-op or more correct, since a mode with
precision N bits can't be expected to hold all of a mode with precision
M>N bits.
The patch changes the branch taken in simplify_subreg for modes with
equal precision, but the new form matches the commentary more closely.
Both branches should be equally good in that situation.
Tested on aarch64-linux-gnu and x86_64-linux-gnu, and by checking that
there were no changes in the testsuite assembly output for one target
per CPU. OK to install?
Richard
2017-08-21 Richard Sandiford <richard.sandif...@linaro.org>
Alan Hayward <alan.hayw...@arm.com>
David Sherwood <david.sherw...@arm.com>
gcc/
* rtl.h (paradoxical_subreg_p): Define inline, and add a version
that takes the outer and inner modes.
* doc/rtl.texi: Use paradoxical_subreg_p instead of a GET_MODE_SIZE
comparison as the canonical test for a paradoxical subreg.
* combine.c (simplify_set): Use paradoxical_subreg_p.
(make_extraction): Likewise.
(force_to_mode): Likewise.
(rtx_equal_for_field_assignment_p): Likewise.
(gen_lowpart_for_combine): Likewise.
(simplify_comparison): Likewise.
* cse.c (equiv_constant): Likewise.
* expmed.c (store_bit_field_1): Likewise.
* final.c (alter_subreg): Likewise.
* fwprop.c (propagate_rtx): Likewise.
(forward_propagate_subreg): Likewise.
* ira-conflicts.c (ira_build_conflicts): Likewise.
* lower-subreg.c (simplify_gen_subreg_concatn): Likewise.
* lra-constraints.c (curr_insn_transform): Likewise.
(split_reg): Likewise.
* lra-eliminations.c (move_plus_up): Likewise.
(lra_eliminate_regs_1): Likewise.
* recog.c (general_operand): Likewise.
* ree.c (combine_reaching_defs): Likewise.
* reload.c (push_reload): Likewise.
(find_reloads): Likewise.
* reload1.c (elimination_effects): Likewise.
(compute_reload_subreg_offset): Likewise.
(choose_reload_regs): Likewise.
* rtlanal.c (subreg_lsb_1): Likewise.
* simplify-rtx.c (simplify_unary_operation_1): Likewise.
(simplify_subreg): Likewise.
* var-tracking.c (track_loc_p): Likewise.
* emit-rtl.c (byte_lowpart_offset): Likewise.
(paradoxical_subreg_p): Delete out-of-line definition.
Index: gcc/rtl.h
===================================================================
--- gcc/rtl.h 2017-08-21 10:42:34.185530464 +0100
+++ gcc/rtl.h 2017-08-21 14:20:43.099964655 +0100
@@ -2784,10 +2784,28 @@ extern rtx operand_subword (rtx, unsigne
/* In emit-rtl.c */
extern rtx operand_subword_force (rtx, unsigned int, machine_mode);
-extern bool paradoxical_subreg_p (const_rtx);
extern int subreg_lowpart_p (const_rtx);
extern unsigned int subreg_size_lowpart_offset (unsigned int, unsigned int);
+/* Return true if a subreg with the given outer and inner modes is
+ paradoxical. */
+
+inline bool
+paradoxical_subreg_p (machine_mode outermode, machine_mode innermode)
+{
+ return GET_MODE_PRECISION (outermode) > GET_MODE_PRECISION (innermode);
+}
+
+/* Return true if X is a paradoxical subreg, false otherwise. */
+
+inline bool
+paradoxical_subreg_p (const_rtx x)
+{
+ if (GET_CODE (x) != SUBREG)
+ return false;
+ return paradoxical_subreg_p (GET_MODE (x), GET_MODE (SUBREG_REG (x)));
+}
+
/* Return the SUBREG_BYTE for an OUTERMODE lowpart of an INNERMODE value. */
inline unsigned int
Index: gcc/doc/rtl.texi
===================================================================
--- gcc/doc/rtl.texi 2017-07-27 10:37:54.486030028 +0100
+++ gcc/doc/rtl.texi 2017-08-21 14:20:43.094947435 +0100
@@ -1872,7 +1872,7 @@ expression is called @dfn{paradoxical}.
class of @code{subreg} is:
@smallexample
-GET_MODE_SIZE (@var{m1}) > GET_MODE_SIZE (@var{m2})
+paradoxical_subreg_p (@var{m1}, @var{m2})
@end smallexample
Paradoxical @code{subreg}s can be used as both lvalues and rvalues.
Index: gcc/combine.c
===================================================================
--- gcc/combine.c 2017-08-21 10:42:34.185530464 +0100
+++ gcc/combine.c 2017-08-21 14:20:43.092940547 +0100
@@ -6809,9 +6809,7 @@ simplify_set (rtx x)
/ UNITS_PER_WORD)
== ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (src)))
+ (UNITS_PER_WORD - 1)) / UNITS_PER_WORD))
- && (WORD_REGISTER_OPERATIONS
- || (GET_MODE_SIZE (GET_MODE (src))
- <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (src)))))
+ && (WORD_REGISTER_OPERATIONS || !paradoxical_subreg_p (src))
#ifdef CANNOT_CHANGE_MODE_CLASS
&& ! (REG_P (dest) && REGNO (dest) < FIRST_PSEUDO_REGISTER
&& REG_CANNOT_CHANGE_MODE_P (REGNO (dest),
@@ -7456,7 +7454,7 @@ make_extraction (machine_mode mode, rtx
: BITS_PER_UNIT)) == 0
/* We can't do this if we are widening INNER_MODE (it
may not be aligned, for one thing). */
- && GET_MODE_PRECISION (inner_mode) >= GET_MODE_PRECISION (tmode)
+ && !paradoxical_subreg_p (tmode, inner_mode)
&& (inner_mode == tmode
|| (! mode_dependent_address_p (XEXP (inner, 0),
MEM_ADDR_SPACE (inner))
@@ -7669,7 +7667,7 @@ make_extraction (machine_mode mode, rtx
/* If bytes are big endian and we had a paradoxical SUBREG, we must
adjust OFFSET to compensate. */
if (BYTES_BIG_ENDIAN
- && GET_MODE_SIZE (inner_mode) < GET_MODE_SIZE (is_mode))
+ && paradoxical_subreg_p (is_mode, inner_mode))
offset -= GET_MODE_SIZE (is_mode) - GET_MODE_SIZE (inner_mode);
/* We can now move to the desired byte. */
@@ -8529,7 +8527,7 @@ force_to_mode (rtx x, machine_mode mode,
/* If X is narrower than MODE and we want all the bits in X's mode, just
get X in the proper mode. */
- if (GET_MODE_SIZE (GET_MODE (x)) < GET_MODE_SIZE (mode)
+ if (paradoxical_subreg_p (mode, GET_MODE (x))
&& (GET_MODE_MASK (GET_MODE (x)) & ~mask) == 0)
return gen_lowpart (mode, x);
@@ -9408,7 +9406,7 @@ rtx_equal_for_field_assignment_p (rtx x,
{
if (widen_x && GET_MODE (x) != GET_MODE (y))
{
- if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (GET_MODE (y)))
+ if (paradoxical_subreg_p (GET_MODE (x), GET_MODE (y)))
return 0;
if (BYTES_BIG_ENDIAN != WORDS_BIG_ENDIAN)
return 0;
@@ -11488,7 +11486,7 @@ gen_lowpart_for_combine (machine_mode om
/* If we want to refer to something bigger than the original memref,
generate a paradoxical subreg instead. That will force a reload
of the original memref X. */
- if (isize < osize)
+ if (paradoxical_subreg_p (omode, imode))
return gen_rtx_SUBREG (omode, x, 0);
if (WORDS_BIG_ENDIAN)
@@ -12145,8 +12143,7 @@ simplify_comparison (enum rtx_code code,
/* If the inner mode is narrower and we are extracting the low part,
we can treat the SUBREG as if it were a ZERO_EXTEND. */
- if (subreg_lowpart_p (op0)
- && GET_MODE_PRECISION (GET_MODE (SUBREG_REG (op0))) < mode_width)
+ if (paradoxical_subreg_p (op0))
;
else if (subreg_lowpart_p (op0)
&& GET_MODE_CLASS (GET_MODE (op0)) == MODE_INT
Index: gcc/cse.c
===================================================================
--- gcc/cse.c 2017-08-21 10:42:34.185530464 +0100
+++ gcc/cse.c 2017-08-21 14:20:43.093943991 +0100
@@ -3802,7 +3802,7 @@ equiv_constant (rtx x)
the subreg. Note that the upper bits of paradoxical subregs
are undefined, so they cannot be said to equal anything. */
if (REG_P (SUBREG_REG (x))
- && GET_MODE_SIZE (mode) <= GET_MODE_SIZE (imode)
+ && !paradoxical_subreg_p (x)
&& (new_rtx = equiv_constant (SUBREG_REG (x))) != 0)
return simplify_subreg (mode, new_rtx, imode, SUBREG_BYTE (x));
Index: gcc/expmed.c
===================================================================
--- gcc/expmed.c 2017-08-21 10:42:34.185530464 +0100
+++ gcc/expmed.c 2017-08-21 14:20:43.095950879 +0100
@@ -736,7 +736,7 @@ store_bit_field_1 (rtx str_rtx, unsigned
int byte_offset = 0;
/* Paradoxical subregs need special handling on big-endian machines. */
- if (SUBREG_BYTE (op0) == 0 && inner_mode_size < outer_mode_size)
+ if (paradoxical_subreg_p (op0))
{
int difference = inner_mode_size - outer_mode_size;
Index: gcc/final.c
===================================================================
--- gcc/final.c 2017-08-21 12:09:48.440614101 +0100
+++ gcc/final.c 2017-08-21 14:20:43.095950879 +0100
@@ -3205,8 +3205,7 @@ alter_subreg (rtx *xp, bool final_p)
/* For paradoxical subregs on big-endian machines, SUBREG_BYTE
contains 0 instead of the proper offset. See simplify_subreg. */
- if (offset == 0
- && GET_MODE_SIZE (GET_MODE (y)) < GET_MODE_SIZE (GET_MODE (x)))
+ if (paradoxical_subreg_p (x))
{
int difference = GET_MODE_SIZE (GET_MODE (y))
- GET_MODE_SIZE (GET_MODE (x));
Index: gcc/fwprop.c
===================================================================
--- gcc/fwprop.c 2017-07-13 09:25:12.152288651 +0100
+++ gcc/fwprop.c 2017-08-21 14:20:43.095950879 +0100
@@ -680,8 +680,7 @@ propagate_rtx (rtx x, machine_mode mode,
|| CONSTANT_P (new_rtx)
|| (GET_CODE (new_rtx) == SUBREG
&& REG_P (SUBREG_REG (new_rtx))
- && (GET_MODE_SIZE (mode)
- <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (new_rtx))))))
+ && !paradoxical_subreg_p (mode, GET_MODE (SUBREG_REG (new_rtx)))))
flags |= PR_CAN_APPEAR;
if (!varying_mem_p (new_rtx))
flags |= PR_HANDLE_MEM;
@@ -1103,9 +1102,7 @@ forward_propagate_subreg (df_ref use, rt
|| !REG_P (SET_DEST (def_set)))
return false;
- /* If this is a paradoxical SUBREG... */
- if (GET_MODE_SIZE (use_mode)
- > GET_MODE_SIZE (GET_MODE (SUBREG_REG (use_reg))))
+ if (paradoxical_subreg_p (use_reg))
{
/* If this is a paradoxical SUBREG, we have no idea what value the
extra bits would have. However, if the operand is equivalent to
Index: gcc/ira-conflicts.c
===================================================================
--- gcc/ira-conflicts.c 2017-02-23 19:54:03.000000000 +0000
+++ gcc/ira-conflicts.c 2017-08-21 14:20:43.095950879 +0100
@@ -775,7 +775,7 @@ ira_build_conflicts (void)
cannot be accessed in the widest mode. */
machine_mode outer_mode = ALLOCNO_WMODE (a);
machine_mode inner_mode = ALLOCNO_MODE (a);
- if (GET_MODE_SIZE (outer_mode) > GET_MODE_SIZE (inner_mode))
+ if (paradoxical_subreg_p (outer_mode, inner_mode))
{
enum reg_class aclass = ALLOCNO_CLASS (a);
for (int j = ira_class_hard_regs_num[aclass] - 1; j >= 0; --j)
Index: gcc/lower-subreg.c
===================================================================
--- gcc/lower-subreg.c 2017-07-13 09:25:13.387236070 +0100
+++ gcc/lower-subreg.c 2017-08-21 14:20:43.096954323 +0100
@@ -661,10 +661,8 @@ simplify_gen_subreg_concatn (machine_mod
if (op2 == NULL_RTX)
{
/* We don't handle paradoxical subregs here. */
- gcc_assert (GET_MODE_SIZE (outermode)
- <= GET_MODE_SIZE (GET_MODE (op)));
- gcc_assert (GET_MODE_SIZE (GET_MODE (op))
- <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (op))));
+ gcc_assert (!paradoxical_subreg_p (outermode, GET_MODE (op)));
+ gcc_assert (!paradoxical_subreg_p (op));
op2 = simplify_subreg_concatn (outermode, SUBREG_REG (op),
byte + SUBREG_BYTE (op));
gcc_assert (op2 != NULL_RTX);
@@ -685,10 +683,7 @@ simplify_gen_subreg_concatn (machine_mod
resolve_simple_move will ask for the high part of the paradoxical
subreg, which does not have a value. Just return a zero. */
if (ret == NULL_RTX
- && GET_CODE (op) == SUBREG
- && SUBREG_BYTE (op) == 0
- && (GET_MODE_SIZE (innermode)
- > GET_MODE_SIZE (GET_MODE (SUBREG_REG (op)))))
+ && paradoxical_subreg_p (op))
return CONST0_RTX (outermode);
gcc_assert (ret != NULL_RTX);
Index: gcc/lra-constraints.c
===================================================================
--- gcc/lra-constraints.c 2017-08-21 10:42:34.185530464 +0100
+++ gcc/lra-constraints.c 2017-08-21 14:20:43.096954323 +0100
@@ -4225,8 +4225,7 @@ curr_insn_transform (bool check_only_p)
/* Strict_low_part requires reload the register not
the sub-register. */
&& (curr_static_id->operand[i].strict_low
- || (GET_MODE_SIZE (mode)
- <= GET_MODE_SIZE (GET_MODE (reg))
+ || (!paradoxical_subreg_p (mode, GET_MODE (reg))
&& (hard_regno
= get_try_hard_regno (REGNO (reg))) >= 0
&& (simplify_subreg_regno
@@ -5465,7 +5464,7 @@ split_reg (bool before_p, int original_r
mode was larger than a register, just use the reg_rtx. Otherwise,
limit the size to that of the biggest access in the function. */
if (mode == VOIDmode
- || GET_MODE_SIZE (mode) > GET_MODE_SIZE (reg_rtx_mode))
+ || paradoxical_subreg_p (mode, reg_rtx_mode))
{
original_reg = regno_reg_rtx[hard_regno];
mode = reg_rtx_mode;
Index: gcc/lra-eliminations.c
===================================================================
--- gcc/lra-eliminations.c 2017-07-05 16:29:19.599861904 +0100
+++ gcc/lra-eliminations.c 2017-08-21 14:20:43.097957767 +0100
@@ -286,8 +286,8 @@ move_plus_up (rtx x)
subreg_reg = SUBREG_REG (x);
x_mode = GET_MODE (x);
subreg_reg_mode = GET_MODE (subreg_reg);
- if (GET_CODE (x) == SUBREG && GET_CODE (subreg_reg) == PLUS
- && GET_MODE_SIZE (x_mode) <= GET_MODE_SIZE (subreg_reg_mode)
+ if (!paradoxical_subreg_p (x)
+ && GET_CODE (subreg_reg) == PLUS
&& CONSTANT_P (XEXP (subreg_reg, 1))
&& GET_MODE_CLASS (x_mode) == MODE_INT
&& GET_MODE_CLASS (subreg_reg_mode) == MODE_INT)
@@ -605,10 +605,7 @@ lra_eliminate_regs_1 (rtx_insn *insn, rt
if (new_rtx != SUBREG_REG (x))
{
- int x_size = GET_MODE_SIZE (GET_MODE (x));
- int new_size = GET_MODE_SIZE (GET_MODE (new_rtx));
-
- if (MEM_P (new_rtx) && x_size <= new_size)
+ if (MEM_P (new_rtx) && !paradoxical_subreg_p (x))
{
SUBREG_REG (x) = new_rtx;
alter_subreg (&x, false);
Index: gcc/recog.c
===================================================================
--- gcc/recog.c 2017-07-13 09:25:12.152288651 +0100
+++ gcc/recog.c 2017-08-21 14:20:43.097957767 +0100
@@ -1002,7 +1002,7 @@ general_operand (rtx op, machine_mode mo
However, we must allow them after reload so that they can
get cleaned up by cleanup_subreg_operands. */
if (!reload_completed && MEM_P (sub)
- && GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (sub)))
+ && paradoxical_subreg_p (op))
return 0;
#endif
/* Avoid memories with nonzero SUBREG_BYTE, as offsetting the memory
@@ -1037,7 +1037,7 @@ general_operand (rtx op, machine_mode mo
size of floating point mode can be less than the integer
mode. */
&& ! lra_in_progress
- && GET_MODE_SIZE (GET_MODE (op)) > GET_MODE_SIZE (GET_MODE (sub)))
+ && paradoxical_subreg_p (op))
return 0;
op = sub;
Index: gcc/ree.c
===================================================================
--- gcc/ree.c 2017-02-23 19:54:20.000000000 +0000
+++ gcc/ree.c 2017-08-21 14:20:43.097957767 +0100
@@ -869,7 +869,8 @@ combine_reaching_defs (ext_cand *cand, c
return false;
for (df_link *use = uses; use; use = use->next)
- if (GET_MODE_PRECISION (GET_MODE (*DF_REF_LOC (use->ref))) > prec)
+ if (paradoxical_subreg_p (GET_MODE (*DF_REF_LOC (use->ref)),
+ GET_MODE (SET_DEST (*dest_sub_rtx))))
return false;
}
Index: gcc/reload.c
===================================================================
--- gcc/reload.c 2017-08-21 10:42:34.185530464 +0100
+++ gcc/reload.c 2017-08-21 14:20:43.098961211 +0100
@@ -1062,13 +1062,12 @@ push_reload (rtx in, rtx out, rtx *inloc
|| (((REG_P (SUBREG_REG (in))
&& REGNO (SUBREG_REG (in)) >= FIRST_PSEUDO_REGISTER)
|| MEM_P (SUBREG_REG (in)))
- && ((GET_MODE_PRECISION (inmode)
- > GET_MODE_PRECISION (GET_MODE (SUBREG_REG (in))))
+ && (paradoxical_subreg_p (inmode, GET_MODE (SUBREG_REG (in)))
|| (GET_MODE_SIZE (inmode) <= UNITS_PER_WORD
&& (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))
<= UNITS_PER_WORD)
- && (GET_MODE_PRECISION (inmode)
- > GET_MODE_PRECISION (GET_MODE (SUBREG_REG (in))))
+ && paradoxical_subreg_p (inmode,
+ GET_MODE (SUBREG_REG (in)))
&& INTEGRAL_MODE_P (GET_MODE (SUBREG_REG (in)))
&& LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (in))) != UNKNOWN)
|| (WORD_REGISTER_OPERATIONS
@@ -1170,8 +1169,7 @@ push_reload (rtx in, rtx out, rtx *inloc
|| (((REG_P (SUBREG_REG (out))
&& REGNO (SUBREG_REG (out)) >= FIRST_PSEUDO_REGISTER)
|| MEM_P (SUBREG_REG (out)))
- && ((GET_MODE_PRECISION (outmode)
- > GET_MODE_PRECISION (GET_MODE (SUBREG_REG (out))))
+ && (paradoxical_subreg_p (outmode, GET_MODE (SUBREG_REG (out)))
|| (WORD_REGISTER_OPERATIONS
&& (GET_MODE_PRECISION (outmode)
< GET_MODE_PRECISION (GET_MODE (SUBREG_REG (out))))
@@ -1299,7 +1297,7 @@ push_reload (rtx in, rtx out, rtx *inloc
if (this_insn_is_asm)
{
machine_mode mode;
- if (GET_MODE_SIZE (inmode) > GET_MODE_SIZE (outmode))
+ if (paradoxical_subreg_p (inmode, outmode))
mode = inmode;
else
mode = outmode;
@@ -3137,15 +3135,15 @@ find_reloads (rtx_insn *insn, int replac
&& (WORD_REGISTER_OPERATIONS
|| ((GET_MODE_BITSIZE (GET_MODE (operand))
< BIGGEST_ALIGNMENT)
- && (GET_MODE_SIZE (operand_mode[i])
- > GET_MODE_SIZE (GET_MODE (operand))))
+ && paradoxical_subreg_p (operand_mode[i],
+ GET_MODE (operand)))
|| BYTES_BIG_ENDIAN
|| ((GET_MODE_SIZE (operand_mode[i])
<= UNITS_PER_WORD)
&& (GET_MODE_SIZE (GET_MODE (operand))
<= UNITS_PER_WORD)
- && (GET_MODE_SIZE (operand_mode[i])
- > GET_MODE_SIZE (GET_MODE (operand)))
+ && paradoxical_subreg_p (operand_mode[i],
+ GET_MODE (operand))
&& INTEGRAL_MODE_P (GET_MODE (operand))
&& LOAD_EXTEND_OP (GET_MODE (operand))
!= UNKNOWN)))
Index: gcc/reload1.c
===================================================================
--- gcc/reload1.c 2017-08-21 10:42:34.185530464 +0100
+++ gcc/reload1.c 2017-08-21 14:20:43.099964655 +0100
@@ -3042,8 +3042,7 @@ elimination_effects (rtx x, machine_mode
case SUBREG:
if (REG_P (SUBREG_REG (x))
- && (GET_MODE_SIZE (GET_MODE (x))
- <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
+ && !paradoxical_subreg_p (x)
&& reg_equivs
&& reg_equiv_memory_loc (REGNO (SUBREG_REG (x))) != 0)
return;
@@ -6373,8 +6372,7 @@ compute_reload_subreg_offset (machine_mo
/* If SUBREG is paradoxical then return the normal lowpart offset
for OUTERMODE and INNERMODE. Our caller has already checked
that OUTERMODE fits in INNERMODE. */
- if (outer_offset == 0
- && GET_MODE_SIZE (outermode) > GET_MODE_SIZE (middlemode))
+ if (paradoxical_subreg_p (outermode, middlemode))
return subreg_lowpart_offset (outermode, innermode);
/* SUBREG is normal, but may not be lowpart; return OUTER_OFFSET
@@ -6664,8 +6662,7 @@ choose_reload_regs (struct insn_chain *c
&& rld[r].out)
/* Don't really use the inherited spill reg
if we need it wider than we've got it. */
- || (GET_MODE_SIZE (rld[r].mode)
- > GET_MODE_SIZE (mode))
+ || paradoxical_subreg_p (rld[r].mode, mode)
|| bad_for_class
/* If find_reloads chose reload_out as reload
Index: gcc/rtlanal.c
===================================================================
--- gcc/rtlanal.c 2017-07-13 09:25:13.516230596 +0100
+++ gcc/rtlanal.c 2017-08-21 14:20:43.101971543 +0100
@@ -3530,7 +3530,7 @@ subreg_lsb_1 (machine_mode outer_mode,
unsigned int word;
/* A paradoxical subreg begins at bit position 0. */
- if (GET_MODE_PRECISION (outer_mode) > GET_MODE_PRECISION (inner_mode))
+ if (paradoxical_subreg_p (outer_mode, inner_mode))
return 0;
if (WORDS_BIG_ENDIAN != BYTES_BIG_ENDIAN)
Index: gcc/simplify-rtx.c
===================================================================
--- gcc/simplify-rtx.c 2017-08-21 10:42:34.185530464 +0100
+++ gcc/simplify-rtx.c 2017-08-21 14:20:43.102974987 +0100
@@ -1465,7 +1465,7 @@ simplify_unary_operation_1 (enum rtx_cod
if (GET_CODE (op) == SUBREG
&& SUBREG_PROMOTED_VAR_P (op)
&& SUBREG_PROMOTED_SIGNED_P (op)
- && GET_MODE_SIZE (mode) <= GET_MODE_SIZE (GET_MODE (XEXP (op, 0))))
+ && !paradoxical_subreg_p (mode, GET_MODE (SUBREG_REG (op))))
{
temp = rtl_hooks.gen_lowpart_no_emit (mode, op);
if (temp)
@@ -1547,7 +1547,7 @@ simplify_unary_operation_1 (enum rtx_cod
if (GET_CODE (op) == SUBREG
&& SUBREG_PROMOTED_VAR_P (op)
&& SUBREG_PROMOTED_UNSIGNED_P (op)
- && GET_MODE_SIZE (mode) <= GET_MODE_SIZE (GET_MODE (XEXP (op, 0))))
+ && !paradoxical_subreg_p (mode, GET_MODE (SUBREG_REG (op))))
{
temp = rtl_hooks.gen_lowpart_no_emit (mode, op);
if (temp)
@@ -6080,7 +6080,7 @@ simplify_subreg (machine_mode outermode,
}
/* See whether resulting subreg will be paradoxical. */
- if (GET_MODE_SIZE (innermostmode) > GET_MODE_SIZE (outermode))
+ if (!paradoxical_subreg_p (outermode, innermostmode))
{
/* In nonparadoxical subregs we can't handle negative offsets. */
if (final_offset < 0)
Index: gcc/var-tracking.c
===================================================================
--- gcc/var-tracking.c 2017-07-13 09:25:13.516230596 +0100
+++ gcc/var-tracking.c 2017-08-21 14:20:43.105985318 +0100
@@ -5295,7 +5295,7 @@ track_loc_p (rtx loc, tree expr, HOST_WI
machine_mode pseudo_mode;
pseudo_mode = PSEUDO_REGNO_MODE (ORIGINAL_REGNO (loc));
- if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (pseudo_mode))
+ if (paradoxical_subreg_p (mode, pseudo_mode))
{
offset += byte_lowpart_offset (pseudo_mode, mode);
mode = pseudo_mode;
@@ -5309,7 +5309,7 @@ track_loc_p (rtx loc, tree expr, HOST_WI
because the real and imaginary parts are represented as separate
pseudo registers, even if the whole complex value fits into one
hard register. */
- if ((GET_MODE_SIZE (mode) > GET_MODE_SIZE (DECL_MODE (expr))
+ if ((paradoxical_subreg_p (mode, DECL_MODE (expr))
|| (store_reg_p
&& !COMPLEX_MODE_P (DECL_MODE (expr))
&& hard_regno_nregs[REGNO (loc)][DECL_MODE (expr)] == 1))
Index: gcc/emit-rtl.c
===================================================================
--- gcc/emit-rtl.c 2017-08-03 10:40:55.518043414 +0100
+++ gcc/emit-rtl.c 2017-08-21 14:20:43.094947435 +0100
@@ -1008,10 +1008,10 @@ gen_rtvec_v (int n, rtx_insn **argp)
byte_lowpart_offset (machine_mode outer_mode,
machine_mode inner_mode)
{
- if (GET_MODE_SIZE (outer_mode) < GET_MODE_SIZE (inner_mode))
- return subreg_lowpart_offset (outer_mode, inner_mode);
- else
+ if (paradoxical_subreg_p (outer_mode, inner_mode))
return -subreg_lowpart_offset (inner_mode, outer_mode);
+ else
+ return subreg_lowpart_offset (outer_mode, inner_mode);
}
/* Generate a REG rtx for a new pseudo register of mode MODE.
@@ -1552,16 +1552,6 @@ subreg_lowpart_p (const_rtx x)
return (subreg_lowpart_offset (GET_MODE (x), GET_MODE (SUBREG_REG (x)))
== SUBREG_BYTE (x));
}
-
-/* Return true if X is a paradoxical subreg, false otherwise. */
-bool
-paradoxical_subreg_p (const_rtx x)
-{
- if (GET_CODE (x) != SUBREG)
- return false;
- return (GET_MODE_PRECISION (GET_MODE (x))
- > GET_MODE_PRECISION (GET_MODE (SUBREG_REG (x))));
-}
/* Return subword OFFSET of operand OP.
The word number, OFFSET, is interpreted as the word number starting
