[PULL 25/42] target/arm: Use tcg_gen_qemu_st_i128 for STZG, STZ2G

Maintainers: Cameron Esfahani <dirty@apple.com>, Roman Bolshakov <r.bolshakov@yadro.com>, Alistair Francis <alistair@alistair23.me>, "Edgar E. Iglesias" <edgar.iglesias@gmail.com>, Peter Maydell <peter.maydell@linaro.org>, Paolo Bonzini <pbonzini@redhat.com>, Beniamino Galvani <b.galvani@gmail.com>, Strahinja Jankovic <strahinja.p.jankovic@gmail.com>, Pavel Pisa <pisa@cmp.felk.cvut.cz>, Vikram Garhwal <fnu.vikram@xilinx.com>, Jason Wang <jasowang@redhat.com>, Francisco Iglesias <francisco.iglesias@amd.com>, Alexander Graf <agraf@csgraf.de>, Cleber Rosa <crosa@redhat.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Wainer dos Santos Moschetta <wainersm@redhat.com>, Beraldo Leal <bleal@redhat.com>, Thomas Huth <thuth@redhat.com>, Laurent Vivier <lvivier@redhat.com>, "Alex Bennée" <alex.bennee@linaro.org>
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[PULL 25/42] target/arm: Use tcg_gen_qemu_st_i128 for STZG, STZ2G
Posted by Peter Maydell 1 year, 11 months ago
From: Richard Henderson <richard.henderson@linaro.org>

This fixes a bug in that these two insns should have been using atomic
16-byte stores, since MTE is ARMv8.5 and LSE2 is mandatory from ARMv8.4.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230530191438.411344-7-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/tcg/translate-a64.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 3674fc1bc16..35eac7729b0 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -4058,15 +4058,18 @@ static void disas_ldst_tag(DisasContext *s, uint32_t insn)
 
     if (is_zero) {
         TCGv_i64 clean_addr = clean_data_tbi(s, addr);
-        TCGv_i64 tcg_zero = tcg_constant_i64(0);
+        TCGv_i64 zero64 = tcg_constant_i64(0);
+        TCGv_i128 zero128 = tcg_temp_new_i128();
         int mem_index = get_mem_index(s);
-        int i, n = (1 + is_pair) << LOG2_TAG_GRANULE;
+        MemOp mop = finalize_memop(s, MO_128 | MO_ALIGN);
 
-        tcg_gen_qemu_st_i64(tcg_zero, clean_addr, mem_index,
-                            MO_UQ | MO_ALIGN_16);
-        for (i = 8; i < n; i += 8) {
-            tcg_gen_addi_i64(clean_addr, clean_addr, 8);
-            tcg_gen_qemu_st_i64(tcg_zero, clean_addr, mem_index, MO_UQ);
+        tcg_gen_concat_i64_i128(zero128, zero64, zero64);
+
+        /* This is 1 or 2 atomic 16-byte operations. */
+        tcg_gen_qemu_st_i128(zero128, clean_addr, mem_index, mop);
+        if (is_pair) {
+            tcg_gen_addi_i64(clean_addr, clean_addr, 16);
+            tcg_gen_qemu_st_i128(zero128, clean_addr, mem_index, mop);
         }
     }
 
-- 
2.34.1