From 6aa5370cccf7c0475192dc8c641450722ae1e477 Mon Sep 17 00:00:00 2001 From: Richard Sandiford Date: Thu, 19 Dec 2019 13:25:22 +0000 Subject: [PATCH] [AArch64] Handle arguments and return types with partial SVE modes Partial SVE modes can be picked up and used by the vector_size(N) attribute.[*] This means that we need to cope with arguments and return values with partial SVE modes, which previously triggered asserts like: /* Generic vectors that map to SVE modes with -msve-vector-bits=N are passed by reference, not by value. */ gcc_assert (!aarch64_sve_mode_p (mode)); The ABI for these types is fixed from pre-SVE days, and must in any case be the same for all -msve-vector-bits=N values. All we need to do is ensure that the vectors are passed and returned in the traditional way. [*] Advanced SIMD always wins for 64-bit and 128-bit vectors though. 2019-12-19 Richard Sandiford gcc/ * config/aarch64/aarch64.c (aarch64_function_value_1): New function, split out from... (aarch64_function_value): ...here. Handle partial SVE modes by pretending that they have the associated/traditional integer mode, then wrap the result in the real mode. (aarch64_layout_arg): Take an orig_mode argument and pass it to aarch64_function_arg_alignment. Handle partial SVE modes analogously to aarch64_function_value. (aarch64_function_arg): Update call accordingly. (aarch64_function_arg_advance): Likewise. gcc/testsuite/ * gcc.target/aarch64/sve/pcs/gnu_vectors_3.c: New test. From-SVN: r279571 --- gcc/ChangeLog | 13 +++ gcc/config/aarch64/aarch64.c | 95 +++++++++++++++---- gcc/testsuite/ChangeLog | 4 + .../aarch64/sve/pcs/gnu_vectors_3.c | 58 +++++++++++ 4 files changed, 150 insertions(+), 20 deletions(-) create mode 100644 gcc/testsuite/gcc.target/aarch64/sve/pcs/gnu_vectors_3.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 5d938ae09d3..63a5ee430db 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,16 @@ +2019-12-19 Richard Sandiford + + * config/aarch64/aarch64.c (aarch64_function_value_1): New function, + split out from... + (aarch64_function_value): ...here. Handle partial SVE modes by + pretending that they have the associated/traditional integer mode, + then wrap the result in the real mode. + (aarch64_layout_arg): Take an orig_mode argument and pass it to + aarch64_function_arg_alignment. Handle partial SVE modes analogously + to aarch64_function_value. + (aarch64_function_arg): Update call accordingly. + (aarch64_function_arg_advance): Likewise. + 2019-12-19 Jan Hubicka Xi Ruoyao diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c index b0aca03bcb4..cf6aa7e4c9f 100644 --- a/gcc/config/aarch64/aarch64.c +++ b/gcc/config/aarch64/aarch64.c @@ -4948,22 +4948,12 @@ aarch64_return_in_msb (const_tree valtype) return true; } -/* Implement TARGET_FUNCTION_VALUE. - Define how to find the value returned by a function. */ - +/* Subroutine of aarch64_function_value. MODE is the mode of the argument + after promotion, and after partial SVE types have been replaced by + their integer equivalents. */ static rtx -aarch64_function_value (const_tree type, const_tree func, - bool outgoing ATTRIBUTE_UNUSED) +aarch64_function_value_1 (const_tree type, machine_mode mode) { - machine_mode mode; - int unsignedp; - int count; - machine_mode ag_mode; - - mode = TYPE_MODE (type); - if (INTEGRAL_TYPE_P (type)) - mode = promote_function_mode (type, mode, &unsignedp, func, 1); - unsigned int num_zr, num_pr; if (type && aarch64_sve_argument_p (type, &num_zr, &num_pr)) { @@ -4998,6 +4988,8 @@ aarch64_function_value (const_tree type, const_tree func, } } + int count; + machine_mode ag_mode; if (aarch64_vfp_is_call_or_return_candidate (mode, type, &ag_mode, &count, NULL)) { @@ -5026,6 +5018,42 @@ aarch64_function_value (const_tree type, const_tree func, return gen_rtx_REG (mode, R0_REGNUM); } +/* Implement TARGET_FUNCTION_VALUE. + Define how to find the value returned by a function. */ + +static rtx +aarch64_function_value (const_tree type, const_tree func, + bool outgoing ATTRIBUTE_UNUSED) +{ + machine_mode mode; + int unsignedp; + + mode = TYPE_MODE (type); + if (INTEGRAL_TYPE_P (type)) + mode = promote_function_mode (type, mode, &unsignedp, func, 1); + + /* Vector types can acquire a partial SVE mode using things like + __attribute__((vector_size(N))), and this is potentially useful. + However, the choice of mode doesn't affect the type's ABI identity, + so we should treat the types as though they had the associated + integer mode, just like they did before SVE was introduced. + + We know that the vector must be 128 bits or smaller, otherwise we'd + have returned it in memory instead. */ + unsigned int vec_flags = aarch64_classify_vector_mode (mode); + if ((vec_flags & VEC_ANY_SVE) && (vec_flags & VEC_PARTIAL)) + { + scalar_int_mode int_mode = int_mode_for_mode (mode).require (); + rtx reg = aarch64_function_value_1 (type, int_mode); + /* Vector types are never returned in the MSB and are never split. */ + gcc_assert (REG_P (reg) && GET_MODE (reg) == int_mode); + rtx pair = gen_rtx_EXPR_LIST (VOIDmode, reg, const0_rtx); + return gen_rtx_PARALLEL (VOIDmode, gen_rtvec (1, pair)); + } + + return aarch64_function_value_1 (type, mode); +} + /* Implements TARGET_FUNCTION_VALUE_REGNO_P. Return true if REGNO is the number of a hard register in which the values of called function may come back. */ @@ -5151,10 +5179,14 @@ aarch64_function_arg_alignment (machine_mode mode, const_tree type, } /* Layout a function argument according to the AAPCS64 rules. The rule - numbers refer to the rule numbers in the AAPCS64. */ + numbers refer to the rule numbers in the AAPCS64. ORIG_MODE is the + mode that was originally given to us by the target hook, whereas the + mode in ARG might be the result of replacing partial SVE modes with + the equivalent integer mode. */ static void -aarch64_layout_arg (cumulative_args_t pcum_v, const function_arg_info &arg) +aarch64_layout_arg (cumulative_args_t pcum_v, const function_arg_info &arg, + machine_mode orig_mode) { CUMULATIVE_ARGS *pcum = get_cumulative_args (pcum_v); tree type = arg.type; @@ -5168,6 +5200,29 @@ aarch64_layout_arg (cumulative_args_t pcum_v, const function_arg_info &arg) if (pcum->aapcs_arg_processed) return; + /* Vector types can acquire a partial SVE mode using things like + __attribute__((vector_size(N))), and this is potentially useful. + However, the choice of mode doesn't affect the type's ABI identity, + so we should treat the types as though they had the associated + integer mode, just like they did before SVE was introduced. + + We know that the vector must be 128 bits or smaller, otherwise we'd + have passed it by reference instead. */ + unsigned int vec_flags = aarch64_classify_vector_mode (mode); + if ((vec_flags & VEC_ANY_SVE) && (vec_flags & VEC_PARTIAL)) + { + function_arg_info tmp_arg = arg; + tmp_arg.mode = int_mode_for_mode (mode).require (); + aarch64_layout_arg (pcum_v, tmp_arg, orig_mode); + if (rtx reg = pcum->aapcs_reg) + { + gcc_assert (REG_P (reg) && GET_MODE (reg) == tmp_arg.mode); + rtx pair = gen_rtx_EXPR_LIST (VOIDmode, reg, const0_rtx); + pcum->aapcs_reg = gen_rtx_PARALLEL (mode, gen_rtvec (1, pair)); + } + return; + } + pcum->aapcs_arg_processed = true; unsigned int num_zr, num_pr; @@ -5289,7 +5344,7 @@ aarch64_layout_arg (cumulative_args_t pcum_v, const function_arg_info &arg) comparison is there because for > 16 * BITS_PER_UNIT alignment nregs should be > 2 and therefore it should be passed by reference rather than value. */ - && (aarch64_function_arg_alignment (mode, type, &abi_break) + && (aarch64_function_arg_alignment (orig_mode, type, &abi_break) == 16 * BITS_PER_UNIT)) { if (abi_break && warn_psabi && currently_expanding_gimple_stmt) @@ -5332,7 +5387,7 @@ aarch64_layout_arg (cumulative_args_t pcum_v, const function_arg_info &arg) on_stack: pcum->aapcs_stack_words = size / UNITS_PER_WORD; - if (aarch64_function_arg_alignment (mode, type, &abi_break) + if (aarch64_function_arg_alignment (orig_mode, type, &abi_break) == 16 * BITS_PER_UNIT) { int new_size = ROUND_UP (pcum->aapcs_stack_size, 16 / UNITS_PER_WORD); @@ -5360,7 +5415,7 @@ aarch64_function_arg (cumulative_args_t pcum_v, const function_arg_info &arg) if (arg.end_marker_p ()) return gen_int_mode (pcum->pcs_variant, DImode); - aarch64_layout_arg (pcum_v, arg); + aarch64_layout_arg (pcum_v, arg, arg.mode); return pcum->aapcs_reg; } @@ -5425,7 +5480,7 @@ aarch64_function_arg_advance (cumulative_args_t pcum_v, || pcum->pcs_variant == ARM_PCS_SIMD || pcum->pcs_variant == ARM_PCS_SVE) { - aarch64_layout_arg (pcum_v, arg); + aarch64_layout_arg (pcum_v, arg, arg.mode); gcc_assert ((pcum->aapcs_reg != NULL_RTX) != (pcum->aapcs_stack_words != 0)); pcum->aapcs_arg_processed = false; diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e66980e0767..3385971dba8 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2019-12-19 Richard Sandiford + + * gcc.target/aarch64/sve/pcs/gnu_vectors_3.c: New test. + 2019-12-19 Feng Xue PR ipa/92794 diff --git a/gcc/testsuite/gcc.target/aarch64/sve/pcs/gnu_vectors_3.c b/gcc/testsuite/gcc.target/aarch64/sve/pcs/gnu_vectors_3.c new file mode 100644 index 00000000000..70c24725de4 --- /dev/null +++ b/gcc/testsuite/gcc.target/aarch64/sve/pcs/gnu_vectors_3.c @@ -0,0 +1,58 @@ +/* { dg-options "-O -msve-vector-bits=256" } */ + +typedef unsigned char int8x4_t __attribute__((vector_size (4))); + +/* +** passthru_x0: +** ret +*/ +int8x4_t passthru_x0 (int8x4_t x0) { return x0; } + +/* +** passthru_x1: +** mov w0, w1 +** ret +*/ +int8x4_t passthru_x1 (int8x4_t x0, int8x4_t x1) { return x1; } + +int8x4_t load (int8x4_t *x0) { return *x0; } + +void store (int8x4_t *x0, int8x4_t x1) { *x0 = x1; } + +/* +** stack_callee: +** ptrue p[0-7], vl32 +** ld1b (z[0-9]+\.d), \1/z, \[sp\] +** st1b \2, \1, \[x0\] +** ret +*/ +__attribute__((noipa)) +void stack_callee (int8x4_t *x0, int8x4_t x1, int8x4_t x2, int8x4_t x3, + int8x4_t x4, int8x4_t x5, int8x4_t x6, int8x4_t x7, + int8x4_t stack0) +{ + *x0 = stack0; +} + +/* +** stack_callee: +** \.\.\. +** ptrue p[0-7], vl32 +** \.\.\. +** ld1b (z[0-9]+\.d), \1/z, \[x0\] +** \.\.\. +** st1b \2, \1, \[sp\] +** \.\.\. +** ret +*/ +void stack_caller (int8x4_t *x0, int8x4_t x1) +{ + stack_callee (x0, x1, x1, x1, x1, x1, x1, x1, *x0); +} + +/* { dg-final { scan-assembler {\tmov\tw2, w} } } */ +/* { dg-final { scan-assembler {\tmov\tw3, w} } } */ +/* { dg-final { scan-assembler {\tmov\tw4, w} } } */ +/* { dg-final { scan-assembler {\tmov\tw5, w} } } */ +/* { dg-final { scan-assembler {\tmov\tw6, w} } } */ +/* { dg-final { scan-assembler {\tmov\tw7, w} } } */ -- 2.30.2