On Mon, Dec 20, 2021 at 12:56 AM HAO CHEN GUI <guih...@linux.ibm.com> wrote:
>
> Hi,
> I modified the patch according to David and Segher's advice.
>
> This patch defines a pattern for mffscrni. If the RN is a constant, it can
> call
> gen_rs6000_mffscrni directly. The "rs6000-builtin-new.def" defines prototype
> for builtin arguments.
> The pattern "rs6000_set_fpscr_rn" is then broken as the mode of its argument
> is DI while its
> corresponding builtin has a const int argument. The patch also fixed it.
>
> Bootstrapped and tested on powerpc64-linux BE and LE with no regressions.
> Is this okay for trunk?
> Any recommendations? Thanks a lot.
>
> ChangeLog
> 2021-12-17 Haochen Gui <guih...@linux.ibm.com>
>
> gcc/
> * config/rs6000/predicates.md (u2bit_cint_operand): Defined.
> * config/rs6000/rs6000-call.c
> (rs6000_expand_set_fpscr_rn_builtin): Not copy argument to a reg if
> it's a constant. The pattern for constant can be recognized now.
> * config/rs6000/rs6000.md (UNSPECV_MFFSCRNI): Defined.
> (rs6000_mffscrni): Defined.
> (rs6000_set_fpscr_rn): Change the type of operand[0] form DI to SI.
> Call gen_rs6000_mffscrni when operand[0] is a const int[0,3].
>
> gcc/testsuite/
> * gcc.target/powerpc/mffscrni_p9.c: New testcase for mffscrni.
> * gcc.target/powerpc/test_fpscr_rn_builtin.c: Modify the test cases to
> test mffscrn and mffscrni separately.
This revised patch is okay.
Thanks, David
>
>
> patch.diff
> diff --git a/gcc/config/rs6000/predicates.md b/gcc/config/rs6000/predicates.md
> index f216ffdf410..b10b4ce6065 100644
> --- a/gcc/config/rs6000/predicates.md
> +++ b/gcc/config/rs6000/predicates.md
> @@ -219,6 +219,11 @@ (define_predicate "u1bit_cint_operand"
> (and (match_code "const_int")
> (match_test "INTVAL (op) >= 0 && INTVAL (op) <= 1")))
>
> +;; Return 1 if op is an unsigned 2-bit constant integer.
> +(define_predicate "u2bit_cint_operand"
> + (and (match_code "const_int")
> + (match_test "INTVAL (op) >= 0 && INTVAL (op) <= 3")))
> +
> ;; Return 1 if op is a unsigned 3-bit constant integer.
> (define_predicate "u3bit_cint_operand"
> (and (match_code "const_int")
> diff --git a/gcc/config/rs6000/rs6000-call.c b/gcc/config/rs6000/rs6000-call.c
> index d9736eaf21c..81261a0f24d 100644
> --- a/gcc/config/rs6000/rs6000-call.c
> +++ b/gcc/config/rs6000/rs6000-call.c
> @@ -9610,13 +9610,15 @@ rs6000_expand_set_fpscr_rn_builtin (enum insn_code
> icode, tree exp)
> compile time if the argument is a variable. The least significant two
> bits of the argument, regardless of type, are used to set the rounding
> mode. All other bits are ignored. */
> - if (CONST_INT_P (op0) && !const_0_to_3_operand(op0, VOIDmode))
> + if (CONST_INT_P (op0))
> {
> - error ("Argument must be a value between 0 and 3.");
> - return const0_rtx;
> + if (!const_0_to_3_operand (op0, VOIDmode))
> + {
> + error ("Argument must be a value between 0 and 3.");
> + return const0_rtx;
> + }
> }
> -
> - if (! (*insn_data[icode].operand[0].predicate) (op0, mode0))
> + else if (! (*insn_data[icode].operand[0].predicate) (op0, mode0))
> op0 = copy_to_mode_reg (mode0, op0);
>
> pat = GEN_FCN (icode) (op0);
> diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
> index 6bec2bddbde..b18746af7ea 100644
> --- a/gcc/config/rs6000/rs6000.md
> +++ b/gcc/config/rs6000/rs6000.md
> @@ -177,6 +177,7 @@ (define_c_enum "unspecv"
> UNSPECV_MFFS ; Move from FPSCR
> UNSPECV_MFFSL ; Move from FPSCR light instruction version
> UNSPECV_MFFSCRN ; Move from FPSCR float rounding mode
> + UNSPECV_MFFSCRNI ; Move from FPSCR float rounding mode with imm
> UNSPECV_MFFSCDRN ; Move from FPSCR decimal float rounding mode
> UNSPECV_MTFSF ; Move to FPSCR Fields 8 to 15
> UNSPECV_MTFSF_HI ; Move to FPSCR Fields 0 to 7
> @@ -6315,6 +6316,14 @@ (define_insn "rs6000_mffscrn"
> "mffscrn %0,%1"
> [(set_attr "type" "fp")])
>
> +(define_insn "rs6000_mffscrni"
> + [(set (match_operand:DF 0 "gpc_reg_operand" "=d")
> + (unspec_volatile:DF [(match_operand:SI 1 "u2bit_cint_operand" "n")]
> + UNSPECV_MFFSCRNI))]
> + "TARGET_P9_MISC"
> + "mffscrni %0,%1"
> + [(set_attr "type" "fp")])
> +
> (define_insn "rs6000_mffscdrn"
> [(set (match_operand:DF 0 "gpc_reg_operand" "=d")
> (unspec_volatile:DF [(const_int 0)] UNSPECV_MFFSCDRN))
> @@ -6324,7 +6333,7 @@ (define_insn "rs6000_mffscdrn"
> [(set_attr "type" "fp")])
>
> (define_expand "rs6000_set_fpscr_rn"
> - [(match_operand:DI 0 "reg_or_cint_operand")]
> + [(match_operand:SI 0 "reg_or_cint_operand")]
> "TARGET_HARD_FLOAT"
> {
> rtx tmp_df = gen_reg_rtx (DFmode);
> @@ -6333,9 +6342,15 @@ (define_expand "rs6000_set_fpscr_rn"
> new rounding mode bits from operands[0][62:63] into FPSCR[62:63]. */
> if (TARGET_P9_MISC)
> {
> - rtx src_df = force_reg (DImode, operands[0]);
> - src_df = simplify_gen_subreg (DFmode, src_df, DImode, 0);
> - emit_insn (gen_rs6000_mffscrn (tmp_df, src_df));
> + if (CONST_INT_P (operands[0])
> + && const_0_to_3_operand (operands[0], VOIDmode))
> + emit_insn (gen_rs6000_mffscrni (tmp_df, operands[0]));
> + else
> + {
> + rtx op0 = convert_to_mode (DImode, operands[0], false);
> + rtx src_df = simplify_gen_subreg (DFmode, op0, DImode, 0);
> + emit_insn (gen_rs6000_mffscrn (tmp_df, src_df));
> + }
> DONE;
> }
>
> @@ -6357,7 +6372,8 @@ (define_expand "rs6000_set_fpscr_rn"
> rtx tmp_di = gen_reg_rtx (DImode);
>
> /* Extract new RN mode from operand. */
> - emit_insn (gen_anddi3 (tmp_rn, operands[0], GEN_INT (0x3)));
> + rtx op0 = convert_to_mode (DImode, operands[0], false);
> + emit_insn (gen_anddi3 (tmp_rn, op0, GEN_INT (0x3)));
>
> /* Insert new RN mode into FSCPR. */
> emit_insn (gen_rs6000_mffs (tmp_df));
> diff --git a/gcc/testsuite/gcc.target/powerpc/mffscrni_p9.c
> b/gcc/testsuite/gcc.target/powerpc/mffscrni_p9.c
> new file mode 100644
> index 00000000000..989a5bcc949
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/powerpc/mffscrni_p9.c
> @@ -0,0 +1,9 @@
> +/* { dg-do compile { target { has_arch_pwr9 } } } */
> +/* { dg-options "-O2" } */
> +/* { dg-final { scan-assembler-times {\mmffscrni\M} 1 } } */
> +
> +void foo ()
> +{
> + int val = 2;
> + __builtin_set_fpscr_rn (val);
> +}
> diff --git a/gcc/testsuite/gcc.target/powerpc/test_fpscr_rn_builtin.c
> b/gcc/testsuite/gcc.target/powerpc/test_fpscr_rn_builtin.c
> index 0d0d3f0f96b..594b458f62c 100644
> --- a/gcc/testsuite/gcc.target/powerpc/test_fpscr_rn_builtin.c
> +++ b/gcc/testsuite/gcc.target/powerpc/test_fpscr_rn_builtin.c
> @@ -8,6 +8,10 @@
> #define RN_MASK 0x3LL /* RN field mask */
>
> void abort (void);
> +void __attribute__ ((noinline)) wrap_set_fpscr_rn (int val)
> +{
> + __builtin_set_fpscr_rn (val);
> +}
>
> int main ()
> {
> @@ -43,7 +47,8 @@ int main ()
> }
>
> /* Test float rounding mode builtin with const value argument. */
> - __builtin_set_fpscr_rn(3);
> + val = 3;
> + __builtin_set_fpscr_rn (val);
> conv_val.d = __builtin_mffs();
> ll_value = conv_val.ll & RN_MASK;
>
> @@ -58,7 +63,7 @@ int main ()
> }
>
> val = 2;
> - __builtin_set_fpscr_rn(val);
> + __builtin_set_fpscr_rn (val);
> conv_val.d = __builtin_mffs();
> ll_value = conv_val.ll & RN_MASK;
>
> @@ -74,7 +79,7 @@ int main ()
>
> /* Reset to 0 for testing */
> val = 0;
> - __builtin_set_fpscr_rn(val);
> + __builtin_set_fpscr_rn (val);
>
> __builtin_mtfsb1(31);
> conv_val.d = __builtin_mffs();
> @@ -157,7 +162,7 @@ int main ()
>
> /* Test builtin float rounding mode with variable as argument. */
> val = 0;
> - __builtin_set_fpscr_rn(val);
> + wrap_set_fpscr_rn (val);
> conv_val.d = __builtin_mffs();
> ll_value = conv_val.ll & RN_MASK;
>
> @@ -172,7 +177,7 @@ int main ()
> }
>
> val = 3;
> - __builtin_set_fpscr_rn(val);
> + wrap_set_fpscr_rn (val);
> conv_val.d = __builtin_mffs();
> ll_value = conv_val.ll & RN_MASK;
>
