[PATCH][GCC-10 Backport] arm: Enable no-writeback vldr.16/vstr.16.
Joe Ramsay
joe.ramsay@arm.com
Wed Aug 5 09:28:53 GMT 2020
From: Joe Ramsay <Joe.Ramsay@arm.com>
Hi,
There was previously no way to specify that a register operand cannot
have any writeback modifiers, and as a result the argument to vldr.16
and vstr.16 could be erroneously output with post-increment. This
change adds a constraint which forbids all writeback, and
selects it in the relevant case for vldr.16 and vstr.16
Bootstrapped on arm-none-eabi. Patch backports cleanly onto gcc-10
branch with no regressions. OK for gcc-10 branch?
Thanks,
Joe
gcc/ChangeLog:
2020-08-04 Joe Ramsay <joe.ramsay@arm.com>
Backported from master
2020-05-20 Joe Ramsay <joe.ramsay@arm.com>
* config/arm/arm-protos.h (arm_coproc_mem_operand_no_writeback):
Declare prototype.
(arm_mve_mode_and_operands_type_check): Declare prototype.
* config/arm/arm.c (arm_coproc_mem_operand): Refactor to use
_arm_coproc_mem_operand.
(arm_coproc_mem_operand_wb): New function to cover full, limited
and no writeback.
(arm_coproc_mem_operand_no_writeback): New constraint for memory
operand with no writeback.
(arm_print_operand): Extend 'E' specifier for memory operand
that does not support writeback.
(arm_mve_mode_and_operands_type_check): New constraint check for
MVE memory operands.
* config/arm/constraints.md: Add Uj constraint for VFP vldr.16
and vstr.16.
* config/arm/vfp.md (*mov_load_vfp_hf16): New pattern for
vldr.16.
(*mov_store_vfp_hf16): New pattern for vstr.16.
(*mov<mode>_vfp_<mode>16): Remove MVE moves.
gcc/testsuite/ChangeLog:
2020-08-04 Joe Ramsay <joe.ramsay@arm.com>
Backported from master
2020-05-20 Joe Ramsay <joe.ramsay@arm.com>
* gcc.target/arm/mve/intrinsics/mve-vldstr16-no-writeback.c: New test.
---
gcc/config/arm/arm-protos.h | 3 +
gcc/config/arm/arm.c | 74 ++++++++++++++++++----
gcc/config/arm/constraints.md | 7 ++
gcc/config/arm/vfp.md | 26 +++++---
.../arm/mve/intrinsics/mve-vldstr16-no-writeback.c | 17 +++++
5 files changed, 105 insertions(+), 22 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/arm/mve/intrinsics/mve-vldstr16-no-writeback.c
diff --git a/gcc/config/arm/arm-protos.h b/gcc/config/arm/arm-protos.h
index 33d162c..e811da4 100644
--- a/gcc/config/arm/arm-protos.h
+++ b/gcc/config/arm/arm-protos.h
@@ -115,8 +115,11 @@ extern enum reg_class coproc_secondary_reload_class (machine_mode, rtx,
extern bool arm_tls_referenced_p (rtx);
extern int arm_coproc_mem_operand (rtx, bool);
+extern int arm_coproc_mem_operand_no_writeback (rtx);
+extern int arm_coproc_mem_operand_wb (rtx, int);
extern int neon_vector_mem_operand (rtx, int, bool);
extern int mve_vector_mem_operand (machine_mode, rtx, bool);
+bool arm_mve_mode_and_operands_type_check (machine_mode, rtx, rtx);
extern int neon_struct_mem_operand (rtx);
extern rtx *neon_vcmla_lane_prepare_operands (rtx *);
diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index a8825ee..d8da167 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -13192,13 +13192,14 @@ neon_element_bits (machine_mode mode)
/* Predicates for `match_operand' and `match_operator'. */
/* Return TRUE if OP is a valid coprocessor memory address pattern.
- WB is true if full writeback address modes are allowed and is false
+ WB level is 2 if full writeback address modes are allowed, 1
if limited writeback address modes (POST_INC and PRE_DEC) are
- allowed. */
+ allowed and 0 if no writeback at all is supported. */
int
-arm_coproc_mem_operand (rtx op, bool wb)
+arm_coproc_mem_operand_wb (rtx op, int wb_level)
{
+ gcc_assert (wb_level == 0 || wb_level == 1 || wb_level == 2);
rtx ind;
/* Reject eliminable registers. */
@@ -13231,16 +13232,18 @@ arm_coproc_mem_operand (rtx op, bool wb)
/* Autoincremment addressing modes. POST_INC and PRE_DEC are
acceptable in any case (subject to verification by
- arm_address_register_rtx_p). We need WB to be true to accept
+ arm_address_register_rtx_p). We need full writeback to accept
+ PRE_INC and POST_DEC, and at least restricted writeback for
PRE_INC and POST_DEC. */
- if (GET_CODE (ind) == POST_INC
- || GET_CODE (ind) == PRE_DEC
- || (wb
- && (GET_CODE (ind) == PRE_INC
- || GET_CODE (ind) == POST_DEC)))
+ if (wb_level > 0
+ && (GET_CODE (ind) == POST_INC
+ || GET_CODE (ind) == PRE_DEC
+ || (wb_level > 1
+ && (GET_CODE (ind) == PRE_INC
+ || GET_CODE (ind) == POST_DEC))))
return arm_address_register_rtx_p (XEXP (ind, 0), 0);
- if (wb
+ if (wb_level > 1
&& (GET_CODE (ind) == POST_MODIFY || GET_CODE (ind) == PRE_MODIFY)
&& arm_address_register_rtx_p (XEXP (ind, 0), 0)
&& GET_CODE (XEXP (ind, 1)) == PLUS
@@ -13262,6 +13265,25 @@ arm_coproc_mem_operand (rtx op, bool wb)
return FALSE;
}
+/* Return TRUE if OP is a valid coprocessor memory address pattern.
+ WB is true if full writeback address modes are allowed and is false
+ if limited writeback address modes (POST_INC and PRE_DEC) are
+ allowed. */
+
+int arm_coproc_mem_operand (rtx op, bool wb)
+{
+ return arm_coproc_mem_operand_wb (op, wb ? 2 : 1);
+}
+
+/* Return TRUE if OP is a valid coprocessor memory address pattern in a
+ context in which no writeback address modes are allowed. */
+
+int
+arm_coproc_mem_operand_no_writeback (rtx op)
+{
+ return arm_coproc_mem_operand_wb (op, 0);
+}
+
/* This function returns TRUE on matching mode and op.
1. For given modes, check for [Rn], return TRUE for Rn <= LO_REGS.
2. For other modes, check for [Rn], return TRUE for Rn < R15 (expect R13). */
@@ -23532,7 +23554,7 @@ arm_print_condition (FILE *stream)
/* Globally reserved letters: acln
Puncutation letters currently used: @_|?().!#
Lower case letters currently used: bcdefhimpqtvwxyz
- Upper case letters currently used: ABCDFGHJKLMNOPQRSTU
+ Upper case letters currently used: ABCDEFGHIJKLMNOPQRSTU
Letters previously used, but now deprecated/obsolete: sVWXYZ.
Note that the global reservation for 'c' is only for CONSTANT_ADDRESS_P.
@@ -24098,11 +24120,12 @@ arm_print_operand (FILE *stream, rtx x, int code)
}
return;
- /* To print the memory operand with "Ux" constraint. Based on the rtx_code
- the memory operands output looks like following.
+ /* To print the memory operand with "Ux" or "Uj" constraint. Based on the
+ rtx_code the memory operands output looks like following.
1. [Rn], #+/-<imm>
2. [Rn, #+/-<imm>]!
- 3. [Rn]. */
+ 3. [Rn, #+/-<imm>]
+ 4. [Rn]. */
case 'E':
{
rtx addr;
@@ -24137,6 +24160,16 @@ arm_print_operand (FILE *stream, rtx x, int code)
asm_fprintf (stream, ", #%wd]!",INTVAL (postinc_reg));
}
}
+ else if (code == PLUS)
+ {
+ rtx base = XEXP (addr, 0);
+ rtx index = XEXP (addr, 1);
+
+ gcc_assert (REG_P (base) && CONST_INT_P (index));
+
+ HOST_WIDE_INT offset = INTVAL (index);
+ asm_fprintf (stream, "[%r, #%wd]", REGNO (base), offset);
+ }
else
{
gcc_assert (REG_P (addr));
@@ -33482,4 +33515,17 @@ arm_mode_base_reg_class (machine_mode mode)
struct gcc_target targetm = TARGET_INITIALIZER;
+bool
+arm_mve_mode_and_operands_type_check (machine_mode mode, rtx op0, rtx op1)
+{
+ if (!(TARGET_HAVE_MVE || TARGET_HAVE_MVE_FLOAT))
+ return true;
+ else if (mode == E_BFmode)
+ return false;
+ else if ((s_register_operand (op0, mode) && MEM_P (op1))
+ || (s_register_operand (op1, mode) && MEM_P (op0)))
+ return false;
+ return true;
+}
+
#include "gt-arm.h"
diff --git a/gcc/config/arm/constraints.md b/gcc/config/arm/constraints.md
index 011badc..ff229aa 100644
--- a/gcc/config/arm/constraints.md
+++ b/gcc/config/arm/constraints.md
@@ -452,6 +452,13 @@
(and (match_code "mem")
(match_test "TARGET_32BIT && arm_coproc_mem_operand (op, FALSE)")))
+(define_memory_constraint "Uj"
+ "@internal
+ In ARM/Thumb-2 state an VFP load/store address which does not support
+ writeback at all (eg vldr.16)."
+ (and (match_code "mem")
+ (match_test "TARGET_32BIT && arm_coproc_mem_operand_no_writeback (op)")))
+
(define_memory_constraint "Uy"
"@internal
In ARM/Thumb-2 state a valid iWMMX load/store address."
diff --git a/gcc/config/arm/vfp.md b/gcc/config/arm/vfp.md
index 3470679..6a2bc5a 100644
--- a/gcc/config/arm/vfp.md
+++ b/gcc/config/arm/vfp.md
@@ -387,6 +387,20 @@
(set_attr "arch" "t2,any,any,any,a,t2,any,any,any,any,any,any")]
)
+(define_insn "*mov_load_vfp_hf16"
+ [(set (match_operand:HF 0 "s_register_operand" "=t")
+ (match_operand:HF 1 "memory_operand" "Uj"))]
+ "TARGET_HAVE_MVE_FLOAT"
+ "vldr.16\\t%0, %E1"
+)
+
+(define_insn "*mov_store_vfp_hf16"
+ [(set (match_operand:HF 0 "memory_operand" "=Uj")
+ (match_operand:HF 1 "s_register_operand" "t"))]
+ "TARGET_HAVE_MVE_FLOAT"
+ "vstr.16\\t%1, %E0"
+)
+
;; HFmode and BFmode moves
(define_insn "*mov<mode>_vfp_<mode>16"
@@ -396,6 +410,8 @@
" m,r,t,r,r,t,Dv,Um,t, F"))]
"TARGET_32BIT
&& TARGET_VFP_FP16INST
+ && arm_mve_mode_and_operands_type_check (<MODE>mode, operands[0],
+ operands[1])
&& (s_register_operand (operands[0], <MODE>mode)
|| s_register_operand (operands[1], <MODE>mode))"
{
@@ -414,15 +430,9 @@
case 6: /* S register from immediate. */
return \"vmov.f16\\t%0, %1\t%@ __<fporbf>\";
case 7: /* S register from memory. */
- if (TARGET_HAVE_MVE)
- return \"vldr.16\\t%0, %A1\";
- else
- return \"vld1.16\\t{%z0}, %A1\";
+ return \"vld1.16\\t{%z0}, %A1\";
case 8: /* Memory from S register. */
- if (TARGET_HAVE_MVE)
- return \"vstr.16\\t%1, %A0\";
- else
- return \"vst1.16\\t{%z1}, %A0\";
+ return \"vst1.16\\t{%z1}, %A0\";
case 9: /* ARM register from constant. */
{
long bits;
diff --git a/gcc/testsuite/gcc.target/arm/mve/intrinsics/mve-vldstr16-no-writeback.c b/gcc/testsuite/gcc.target/arm/mve/intrinsics/mve-vldstr16-no-writeback.c
new file mode 100644
index 0000000..0a69ace
--- /dev/null
+++ b/gcc/testsuite/gcc.target/arm/mve/intrinsics/mve-vldstr16-no-writeback.c
@@ -0,0 +1,17 @@
+/* { dg-require-effective-target arm_v8_1m_mve_fp_ok } */
+/* { dg-add-options arm_v8_1m_mve_fp } */
+/* { dg-additional-options "-O2" } */
+
+void
+fn1 (__fp16 *pSrc)
+{
+ __fp16 high;
+ __fp16 *pDst = 0;
+ unsigned i;
+ for (i = 0;; i++)
+ if (pSrc[i])
+ pDst[i] = high;
+}
+
+/* { dg-final { scan-assembler {vldr\.16\ts[0-9]+, \[r[0-9]+\]\n} } } */
+/* { dg-final { scan-assembler {vstr\.16\ts[0-9]+, \[r[0-9]+\]\n} } } */
--
2.7.4
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