From c0d86060f033fc8d591b0163e380ff6cd04f213a Mon Sep 17 00:00:00 2001 From: Taylor Simpson Date: Wed, 9 Feb 2022 18:15:56 -0800 Subject: [PATCH] Hexagon (target/hexagon) assignment to c4 should wait until packet commit On Hexagon, c4 is an alias for predicate registers P3:0. If we assign to c4 inside a packet with reads from predicate registers, the predicate reads should get the old values. Test case added to tests/tcg/hexagon/preg_alias.c Co-authored-by: Michael Lambert Signed-off-by: Taylor Simpson Message-Id: <20220210021556.9217-13-tsimpson@quicinc.com> Reviewed-by: Richard Henderson --- target/hexagon/genptr.c | 14 ++++++++----- tests/tcg/hexagon/preg_alias.c | 38 ++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+), 5 deletions(-) diff --git a/target/hexagon/genptr.c b/target/hexagon/genptr.c index 4419d30e23..cd6af4bceb 100644 --- a/target/hexagon/genptr.c +++ b/target/hexagon/genptr.c @@ -1,5 +1,5 @@ /* - * Copyright(c) 2019-2021 Qualcomm Innovation Center, Inc. All Rights Reserved. + * Copyright(c) 2019-2022 Qualcomm Innovation Center, Inc. All Rights Reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by @@ -210,11 +210,15 @@ static inline void gen_read_ctrl_reg_pair(DisasContext *ctx, const int reg_num, } } -static inline void gen_write_p3_0(TCGv control_reg) +static void gen_write_p3_0(DisasContext *ctx, TCGv control_reg) { + TCGv hex_p8 = tcg_temp_new(); for (int i = 0; i < NUM_PREGS; i++) { - tcg_gen_extract_tl(hex_pred[i], control_reg, i * 8, 8); + tcg_gen_extract_tl(hex_p8, control_reg, i * 8, 8); + gen_log_pred_write(ctx, i, hex_p8); + ctx_log_pred_write(ctx, i); } + tcg_temp_free(hex_p8); } /* @@ -228,7 +232,7 @@ static inline void gen_write_ctrl_reg(DisasContext *ctx, int reg_num, TCGv val) { if (reg_num == HEX_REG_P3_0) { - gen_write_p3_0(val); + gen_write_p3_0(ctx, val); } else { gen_log_reg_write(reg_num, val); ctx_log_reg_write(ctx, reg_num); @@ -250,7 +254,7 @@ static inline void gen_write_ctrl_reg_pair(DisasContext *ctx, int reg_num, if (reg_num == HEX_REG_P3_0) { TCGv val32 = tcg_temp_new(); tcg_gen_extrl_i64_i32(val32, val); - gen_write_p3_0(val32); + gen_write_p3_0(ctx, val32); tcg_gen_extrh_i64_i32(val32, val); gen_log_reg_write(reg_num + 1, val32); tcg_temp_free(val32); diff --git a/tests/tcg/hexagon/preg_alias.c b/tests/tcg/hexagon/preg_alias.c index 79febeca97..b44a8112b4 100644 --- a/tests/tcg/hexagon/preg_alias.c +++ b/tests/tcg/hexagon/preg_alias.c @@ -97,6 +97,42 @@ static inline void creg_alias_pair(unsigned int cval, PRegs *pregs) check(c5, 0xdeadbeef); } +static void test_packet(void) +{ + /* + * Test that setting c4 inside a packet doesn't impact the predicates + * that are read during the packet. + */ + + int result; + int old_val = 0x0000001c; + + /* Test a predicated register transfer */ + result = old_val; + asm ( + "c4 = %1\n\t" + "{\n\t" + " c4 = %2\n\t" + " if (!p2) %0 = %3\n\t" + "}\n\t" + : "+r"(result) + : "r"(0xffffffff), "r"(0xff00ffff), "r"(0x837ed653) + : "p0", "p1", "p2", "p3"); + check(result, old_val); + + /* Test a predicated store */ + result = 0xffffffff; + asm ("c4 = %0\n\t" + "{\n\t" + " c4 = %1\n\t" + " if (!p2) memw(%2) = #0\n\t" + "}\n\t" + : + : "r"(0), "r"(0xffffffff), "r"(&result) + : "p0", "p1", "p2", "p3", "memory"); + check(result, 0x0); +} + int main() { int c4; @@ -162,6 +198,8 @@ int main() creg_alias_pair(0xffffffff, &pregs); check(pregs.creg, 0xffffffff); + test_packet(); + puts(err ? "FAIL" : "PASS"); return err; }