From 01061eff3ffb7c1569429c11db1c75a05e844a86 Mon Sep 17 00:00:00 2001 From: Philipp Tomsich Date: Sat, 12 Nov 2022 22:29:39 +0100 Subject: [PATCH] RISC-V: Support noce_try_store_flag_mask as vt.maskc When if-conversion in noce_try_store_flag_mask starts the sequence off with an order-operator, our patterns for vt.maskc will receive the result of the order-operator as a register argument; consequently, they can't know that the result will be either 1 or 0. To convey this information (and make vt.maskc applicable), we wrap the result of the order-operator in a eq/ne against (const_int 0). This commit adds the split pattern to handle these cases. gcc/ChangeLog: * config/riscv/xventanacondops.md: Add split to wrap an an order-operator suitably for generating vt.maskc. Signed-off-by: Philipp Tomsich Ref vrull/gcc#157 RISC-V: Recognize 'ge'/'le' operators as 'slt'/'sgt' During if-conversion, if noce_try_store_flag_mask succeeds, we may see if (cur < next) { next = 0; } transformed into 27: r82:SI=ltu(r76:DI,r75:DI) REG_DEAD r76:DI 28: r81:SI=r82:SI^0x1 REG_DEAD r82:SI 29: r80:DI=zero_extend(r81:SI) REG_DEAD r81:SI This currently escapes the combiner, as RISC-V does not have a pattern to apply the 'slt' instruction to 'geu' verbs. By adding a pattern in this commit, we match such cases. gcc/ChangeLog: * config/riscv/predicates.md (anyge_operator): Define. (anygt_operator): Define. (anyle_operator): Define. (anylt_operator): Define. * config/riscv/riscv.md (*sge_): Add a pattern to map 'geu' onto slt w/ reversed operands. * config/riscv/riscv.md: Helpers for ge & le. gcc/testsuite/ChangeLog: * gcc.target/riscv/xventanacondops-le-01.c: New test. * gcc.target/riscv/xventanacondops-lt-03.c: New test. --- gcc/config/riscv/predicates.md | 12 +++++ gcc/config/riscv/riscv.md | 26 +++++++++++ gcc/config/riscv/xventanacondops.md | 45 +++++++++++++++++++ .../gcc.target/riscv/xventanacondops-le-01.c | 17 +++++++ .../gcc.target/riscv/xventanacondops-lt-03.c | 17 +++++++ 5 files changed, 117 insertions(+) create mode 100644 gcc/testsuite/gcc.target/riscv/xventanacondops-le-01.c create mode 100644 gcc/testsuite/gcc.target/riscv/xventanacondops-lt-03.c diff --git a/gcc/config/riscv/predicates.md b/gcc/config/riscv/predicates.md index c2ff41bb0fd8..3c74996e4dff 100644 --- a/gcc/config/riscv/predicates.md +++ b/gcc/config/riscv/predicates.md @@ -200,6 +200,18 @@ (define_predicate "equality_operator" (match_code "eq,ne")) +(define_predicate "anyge_operator" + (match_code "ge,geu")) + +(define_predicate "anygt_operator" + (match_code "gt,gtu")) + +(define_predicate "anyle_operator" + (match_code "le,leu")) + +(define_predicate "anylt_operator" + (match_code "lt,ltu")) + (define_predicate "order_operator" (match_code "eq,ne,lt,ltu,le,leu,ge,geu,gt,gtu")) diff --git a/gcc/config/riscv/riscv.md b/gcc/config/riscv/riscv.md index fff55af9e088..483cd1faf033 100644 --- a/gcc/config/riscv/riscv.md +++ b/gcc/config/riscv/riscv.md @@ -2449,6 +2449,19 @@ [(set_attr "type" "slt") (set_attr "mode" "")]) +(define_split + [(set (match_operand:GPR 0 "register_operand") + (match_operator:GPR 1 "anyle_operator" + [(match_operand:X 2 "register_operand") + (match_operand:X 3 "register_operand")]))] + "TARGET_XVENTANACONDOPS" + [(set (match_dup 0) (match_dup 4)) + (set (match_dup 0) (eq:GPR (match_dup 0) (const_int 0)))] + { + operands[4] = gen_rtx_fmt_ee (GET_CODE (operands[1]) == LE ? LT : LTU, + mode, operands[3], operands[2]); + }) + (define_insn "*slt_" [(set (match_operand:GPR 0 "register_operand" "= r") (any_lt:GPR (match_operand:X 1 "register_operand" " r") @@ -2470,6 +2483,19 @@ [(set_attr "type" "slt") (set_attr "mode" "")]) +(define_split + [(set (match_operand:GPR 0 "register_operand") + (match_operator:GPR 1 "anyge_operator" + [(match_operand:X 2 "register_operand") + (match_operand:X 3 "register_operand")]))] + "TARGET_XVENTANACONDOPS" + [(set (match_dup 0) (match_dup 4)) + (set (match_dup 0) (eq:GPR (match_dup 0) (const_int 0)))] +{ + operands[4] = gen_rtx_fmt_ee (GET_CODE (operands[1]) == GE ? LT : LTU, + mode, operands[2], operands[3]); +}) + ;; ;; .................... ;; diff --git a/gcc/config/riscv/xventanacondops.md b/gcc/config/riscv/xventanacondops.md index 641cef0e44e4..7930ef1d837f 100644 --- a/gcc/config/riscv/xventanacondops.md +++ b/gcc/config/riscv/xventanacondops.md @@ -28,3 +28,48 @@ (match_operand:DI 2 "register_operand" "r")))] "TARGET_XVENTANACONDOPS" "vt.maskc\t%0,%2,%1") + +;; Make order operators digestible to the vt.maskc logic by +;; wrapping their result in a comparison against (const_int 0). + +;; "a >= b" is "!(a < b)" +(define_split + [(set (match_operand:X 0 "register_operand") + (and:X (neg:X (match_operator:X 1 "anyge_operator" + [(match_operand:X 2 "register_operand") + (match_operand:X 3 "register_operand")])) + (match_operand:X 4 "register_operand"))) + (clobber (match_operand:X 5 "register_operand"))] + "TARGET_XVENTANACONDOPS" + [(set (match_dup 5) (match_dup 6)) + (set (match_dup 0) (and:X (neg:X (eq:X (match_dup 5) (const_int 0))) + (match_dup 4)))] +{ + operands[6] = gen_rtx_fmt_ee (GET_CODE (operands[1]) == GE ? LT : LTU, + mode, operands[2], operands[3]); +}) + +;; "a > b" +(define_split + [(set (match_operand:X 0 "register_operand") + (and:X (neg:X (match_operator:X 1 "anygt_operator" + [(match_operand:X 2 "register_operand") + (match_operand:X 3 "register_operand")])) + (match_operand:X 4 "register_operand"))) + (clobber (match_operand:X 5 "register_operand"))] + "TARGET_XVENTANACONDOPS" + [(set (match_dup 5) (match_dup 1)) + (set (match_dup 0) (and:X (neg:X (ne:X (match_dup 5) (const_int 0))) + (match_dup 4)))]) + +;; "a <= b" is "!(a > b)" +(define_split + [(set (match_operand:X 0 "register_operand") + (and:X (neg:X (match_operator:X 1 "anyle_operator" + [(match_operand:X 2 "register_operand") + (match_operand:X 3 "arith_operand")])) + (match_operand:X 4 "register_operand"))) + (clobber (match_operand:X 5 "register_operand"))] + "TARGET_XVENTANACONDOPS" + [(set (match_dup 5) (match_dup 1)) + (set (match_dup 0) (and:X (neg:X (ne:X (match_dup 5) (const_int 0))) diff --git a/gcc/testsuite/gcc.target/riscv/xventanacondops-le-01.c b/gcc/testsuite/gcc.target/riscv/xventanacondops-le-01.c new file mode 100644 index 000000000000..231b570158ad --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/xventanacondops-le-01.c @@ -0,0 +1,17 @@ +/* { dg-do compile } */ +/* { dg-options "-march=rv64gc_zba_zbb_zbs_xventanacondops -mabi=lp64 -mbranch-cost=4" } */ +/* { dg-skip-if "" { *-*-* } { "-O0" "-Og" "-O1" "-Os" "-Oz" } } */ + +long long sink (long long); + +long long lt3 (long long a, long long b) +{ + if (a <= b) + b = 0; + + return sink(b); +} + +/* { dg-final { scan-assembler-times "sgt\t" 1 } } */ +/* { dg-final { scan-assembler-times "vt.maskc\t" 1 } } */ + diff --git a/gcc/testsuite/gcc.target/riscv/xventanacondops-lt-03.c b/gcc/testsuite/gcc.target/riscv/xventanacondops-lt-03.c new file mode 100644 index 000000000000..b693521ba2f4 --- /dev/null +++ b/gcc/testsuite/gcc.target/riscv/xventanacondops-lt-03.c @@ -0,0 +1,17 @@ +/* { dg-do compile } */ +/* { dg-options "-march=rv64gc_zba_zbb_zbs_xventanacondops -mabi=lp64 -mbranch-cost=4" } */ +/* { dg-skip-if "" { *-*-* } { "-O0" "-Og" "-O1" "-Os" "-Oz" } } */ + +long long sink (long long); + +long long lt3 (long long a, long long b) +{ + if (a < b) + b = 0; + + return sink(b); +} + +/* { dg-final { scan-assembler-times "slt\t" 1 } } */ +/* { dg-final { scan-assembler-times "vt.maskcn\t" 1 } } */ +