From: Saleem Abdulrasool <abdulras@google.com>
To: qemu-devel@nongnu.org
Cc: qemu-riscv@nongnu.org, palmer@dabbelt.com,
alistair.francis@wdc.com, bin.meng@windriver.com,
frank.chang@sifive.com,
Saleem Abdulrasool <compnerd@compnerd.org>
Subject: [PATCH] riscv: do not set the rounding mode via `gen_set_rm`
Date: Thu, 29 Dec 2022 17:37:43 +0000 [thread overview]
Message-ID: <20221229173743.123894-1-abdulras@google.com> (raw)
From: Saleem Abdulrasool <compnerd@compnerd.org>
Setting the rounding mode via the `gen_set_rm` call would alter the
state of the disassembler, resetting the `TransOp` in the assembler
context. When we subsequently set the rounding mode to the desired
value, we would trigger an assertion in `decode_save_opc`. Instead
we can set the rounding mode via the `gen_helper_set_rounding_mode`
which will still trigger the exception in the case of an invalid RM
without altering the CPU disassembler state.
Signed-off-by: Saleem Abdulrasool <compnerd@compnerd.org>
---
target/riscv/insn_trans/trans_rvv.c.inc | 69 +++++++++++++------------
1 file changed, 36 insertions(+), 33 deletions(-)
diff --git a/target/riscv/insn_trans/trans_rvv.c.inc b/target/riscv/insn_trans/trans_rvv.c.inc
index 4dea4413ae..73f6fab1c5 100644
--- a/target/riscv/insn_trans/trans_rvv.c.inc
+++ b/target/riscv/insn_trans/trans_rvv.c.inc
@@ -2679,8 +2679,10 @@ static bool do_opfv(DisasContext *s, arg_rmr *a,
int rm)
{
if (checkfn(s, a)) {
+ // the helper will raise an exception if the rounding mode is invalid
if (rm != RISCV_FRM_DYN) {
- gen_set_rm(s, RISCV_FRM_DYN);
+ gen_helper_set_rounding_mode(cpu_env,
+ tcg_constant_i32(RISCV_FRM_DYN));
}
uint32_t data = 0;
@@ -3001,38 +3003,39 @@ static bool opffv_narrow_check(DisasContext *s, arg_rmr *a)
require_scale_zve64f(s);
}
-#define GEN_OPFV_NARROW_TRANS(NAME, CHECK, HELPER, FRM) \
-static bool trans_##NAME(DisasContext *s, arg_rmr *a) \
-{ \
- if (CHECK(s, a)) { \
- if (FRM != RISCV_FRM_DYN) { \
- gen_set_rm(s, RISCV_FRM_DYN); \
- } \
- \
- uint32_t data = 0; \
- static gen_helper_gvec_3_ptr * const fns[2] = { \
- gen_helper_##HELPER##_h, \
- gen_helper_##HELPER##_w, \
- }; \
- TCGLabel *over = gen_new_label(); \
- gen_set_rm(s, FRM); \
- tcg_gen_brcondi_tl(TCG_COND_EQ, cpu_vl, 0, over); \
- tcg_gen_brcond_tl(TCG_COND_GEU, cpu_vstart, cpu_vl, over); \
- \
- data = FIELD_DP32(data, VDATA, VM, a->vm); \
- data = FIELD_DP32(data, VDATA, LMUL, s->lmul); \
- data = FIELD_DP32(data, VDATA, VTA, s->vta); \
- data = FIELD_DP32(data, VDATA, VMA, s->vma); \
- tcg_gen_gvec_3_ptr(vreg_ofs(s, a->rd), vreg_ofs(s, 0), \
- vreg_ofs(s, a->rs2), cpu_env, \
- s->cfg_ptr->vlen / 8, \
- s->cfg_ptr->vlen / 8, data, \
- fns[s->sew - 1]); \
- mark_vs_dirty(s); \
- gen_set_label(over); \
- return true; \
- } \
- return false; \
+#define GEN_OPFV_NARROW_TRANS(NAME, CHECK, HELPER, FRM) \
+static bool trans_##NAME(DisasContext *s, arg_rmr *a) \
+{ \
+ if (CHECK(s, a)) { \
+ if (FRM != RISCV_FRM_DYN) { \
+ gen_helper_set_rounding_mode(cpu_env, \
+ tcg_constant_i32(RISCV_FRM_DYN)); \
+ } \
+ \
+ uint32_t data = 0; \
+ static gen_helper_gvec_3_ptr * const fns[2] = { \
+ gen_helper_##HELPER##_h, \
+ gen_helper_##HELPER##_w, \
+ }; \
+ TCGLabel *over = gen_new_label(); \
+ gen_set_rm(s, FRM); \
+ tcg_gen_brcondi_tl(TCG_COND_EQ, cpu_vl, 0, over); \
+ tcg_gen_brcond_tl(TCG_COND_GEU, cpu_vstart, cpu_vl, over); \
+ \
+ data = FIELD_DP32(data, VDATA, VM, a->vm); \
+ data = FIELD_DP32(data, VDATA, LMUL, s->lmul); \
+ data = FIELD_DP32(data, VDATA, VTA, s->vta); \
+ data = FIELD_DP32(data, VDATA, VMA, s->vma); \
+ tcg_gen_gvec_3_ptr(vreg_ofs(s, a->rd), vreg_ofs(s, 0), \
+ vreg_ofs(s, a->rs2), cpu_env, \
+ s->cfg_ptr->vlen / 8, \
+ s->cfg_ptr->vlen / 8, data, \
+ fns[s->sew - 1]); \
+ mark_vs_dirty(s); \
+ gen_set_label(over); \
+ return true; \
+ } \
+ return false; \
}
GEN_OPFV_NARROW_TRANS(vfncvt_f_xu_w, opfxv_narrow_check, vfncvt_f_xu_w,
--
2.39.0.314.g84b9a713c41-goog
next reply other threads:[~2022-12-29 17:38 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-12-29 17:37 Saleem Abdulrasool [this message]
2022-12-29 18:01 ` [PATCH] riscv: do not set the rounding mode via `gen_set_rm` Philippe Mathieu-Daudé
-- strict thread matches above, loose matches on Subject: below --
2022-12-29 17:27 Saleem Abdulrasool
2023-01-08 3:52 ` Bin Meng
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