target/arm: Introduce delay_exception{_el}

Add infrastructure to raise an exception out of line.

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20251008215613.300150-44-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 1337e16a96be5b9b2c3129145877de427e2f2201..c037119cdf9245c785cf07bd54152515f416db85 100644 (file)
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -10601,6 +10601,8 @@ static void aarch64_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             break;
         }
     }
+
+    emit_delayed_exceptions(dc);
 }
 
 const TranslatorOps aarch64_translator_ops = {

diff --git a/target/arm/tcg/translate.c b/target/arm/tcg/translate.c
index e62dcc5d85d5a85396f60419e23db0f0c354e4c1..78d26aac043de9e19ef93aba18f1a2e164ae2d34 100644 (file)
--- a/target/arm/tcg/translate.c
+++ b/target/arm/tcg/translate.c
@@ -1088,6 +1088,57 @@ void gen_exception_insn(DisasContext *s, target_long pc_diff,
     s->base.is_jmp = DISAS_NORETURN;
 }
 
+TCGLabel *delay_exception_el(DisasContext *s, int excp,
+                             uint32_t syn, uint32_t target_el)
+{
+    /* Use tcg_malloc for automatic release on longjmp out of translation. */
+    DisasDelayException *e = tcg_malloc(sizeof(DisasDelayException));
+
+    memset(e, 0, sizeof(*e));
+
+    /* Save enough of the current state to satisfy gen_exception_insn. */
+    e->pc_curr = s->pc_curr;
+    e->pc_save = s->pc_save;
+    if (!s->aarch64) {
+        e->condexec_cond = s->condexec_cond;
+        e->condexec_mask = s->condexec_mask;
+    }
+
+    e->excp = excp;
+    e->syn = syn;
+    e->target_el = target_el;
+
+    e->next = s->delay_excp_list;
+    s->delay_excp_list = e;
+
+    e->lab = gen_new_label();
+    return e->lab;
+}
+
+TCGLabel *delay_exception(DisasContext *s, int excp, uint32_t syn)
+{
+    return delay_exception_el(s, excp, syn, 0);
+}
+
+void emit_delayed_exceptions(DisasContext *s)
+{
+    for (DisasDelayException *e = s->delay_excp_list; e ; e = e->next) {
+        gen_set_label(e->lab);
+
+        /* Restore the insn state to satisfy gen_exception_insn. */
+        s->pc_curr = e->pc_curr;
+        s->pc_save = e->pc_save;
+        s->condexec_cond = e->condexec_cond;
+        s->condexec_mask = e->condexec_mask;
+
+        if (e->target_el) {
+            gen_exception_insn_el(s, 0, e->excp, e->syn, e->target_el);
+        } else {
+            gen_exception_insn(s, 0, e->excp, e->syn);
+        }
+    }
+}
+
 static void gen_exception_bkpt_insn(DisasContext *s, uint32_t syn)
 {
     gen_set_condexec(s);
@@ -6791,6 +6842,8 @@ static void arm_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
             gen_goto_tb(dc, 1, curr_insn_len(dc));
         }
     }
+
+    emit_delayed_exceptions(dc);
 }
 
 static const TranslatorOps arm_translator_ops = {

diff --git a/target/arm/tcg/translate.h b/target/arm/tcg/translate.h
index 943dfd45fe7be030cbdc8de0ae833dd17bace539..9a85ea74dbb6a92568b4acf776bb094dcea85fd7 100644 (file)
--- a/target/arm/tcg/translate.h
+++ b/target/arm/tcg/translate.h
@@ -21,9 +21,25 @@ typedef struct DisasLabel {
     target_ulong pc_save;
 } DisasLabel;
 
+/*
+ * Emit an exception call out of line.
+ */
+typedef struct DisasDelayException {
+    struct DisasDelayException *next;
+    TCGLabel *lab;
+    target_long pc_curr;
+    target_long pc_save;
+    int condexec_mask;
+    int condexec_cond;
+    uint32_t excp;
+    uint32_t syn;
+    uint32_t target_el;
+} DisasDelayException;
+
 typedef struct DisasContext {
     DisasContextBase base;
     const ARMISARegisters *isar;
+    DisasDelayException *delay_excp_list;
 
     /* The address of the current instruction being translated. */
     target_ulong pc_curr;
@@ -365,6 +381,10 @@ void gen_exception_insn_el(DisasContext *s, target_long pc_diff, int excp,
                            uint32_t syn, uint32_t target_el);
 void gen_exception_insn(DisasContext *s, target_long pc_diff,
                         int excp, uint32_t syn);
+TCGLabel *delay_exception_el(DisasContext *s, int excp,
+                             uint32_t syn, uint32_t target_el);
+TCGLabel *delay_exception(DisasContext *s, int excp, uint32_t syn);
+void emit_delayed_exceptions(DisasContext *s);
 
 /* Return state of Alternate Half-precision flag, caller frees result */
 static inline TCGv_i32 get_ahp_flag(void)