target/xtensa: statically allocate xtensa_insnbufs in DisasContext

Rather than dynamically allocate, and risk failing to free
when we longjmp out of the translator, allocate the maximum
buffer size based on the maximum supported instruction length.

Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Richard Henderson <richard.henderson@linaro.org>

diff --git a/target/xtensa/cpu.h b/target/xtensa/cpu.h
index c0d69fad96c59f91f1ec8b10b20db04c4f09806a..7a46dccbe11b05e9565192b9e24271f0d7b0f24b 100644 (file)
--- a/target/xtensa/cpu.h
+++ b/target/xtensa/cpu.h
@@ -213,6 +213,9 @@ enum {
 #define MEMCTL_IL0EN 0x1
 
 #define MAX_INSN_LENGTH 64
+#define MAX_INSNBUF_LENGTH \
+    ((MAX_INSN_LENGTH + sizeof(xtensa_insnbuf_word) - 1) / \
+     sizeof(xtensa_insnbuf_word))
 #define MAX_INSN_SLOTS 32
 #define MAX_OPCODE_ARGS 16
 #define MAX_NAREG 64

diff --git a/target/xtensa/helper.c b/target/xtensa/helper.c
index 376a61f3397c6df104d9f68eb235c6bc3ae12a5d..7073381f03b2469d9958d2bc1afbae2096b0475b 100644 (file)
--- a/target/xtensa/helper.c
+++ b/target/xtensa/helper.c
@@ -96,6 +96,7 @@ static void init_libisa(XtensaConfig *config)
 
     config->isa = xtensa_isa_init(config->isa_internal, NULL, NULL);
     assert(xtensa_isa_maxlength(config->isa) <= MAX_INSN_LENGTH);
+    assert(xtensa_insnbuf_size(config->isa) <= MAX_INSNBUF_LENGTH);
     opcodes = xtensa_isa_num_opcodes(config->isa);
     formats = xtensa_isa_num_formats(config->isa);
     regfiles = xtensa_isa_num_regfiles(config->isa);

diff --git a/target/xtensa/translate.c b/target/xtensa/translate.c
index 1010c1ca876776ac0f4004fa325ae4e353c26e84..e0beaf7abbbd2e7d3305bb9275915804cd533755 100644 (file)
--- a/target/xtensa/translate.c
+++ b/target/xtensa/translate.c
@@ -72,8 +72,8 @@ struct DisasContext {
     unsigned cpenable;
 
     uint32_t op_flags;
-    xtensa_insnbuf insnbuf;
-    xtensa_insnbuf slotbuf;
+    xtensa_insnbuf_word insnbuf[MAX_INSNBUF_LENGTH];
+    xtensa_insnbuf_word slotbuf[MAX_INSNBUF_LENGTH];
 };
 
 static TCGv_i32 cpu_pc;
@@ -1173,16 +1173,6 @@ static void xtensa_tr_init_disas_context(DisasContextBase *dcbase,
     dc->cwoe = tb_flags & XTENSA_TBFLAG_CWOE;
     dc->callinc = ((tb_flags & XTENSA_TBFLAG_CALLINC_MASK) >>
                    XTENSA_TBFLAG_CALLINC_SHIFT);
-
-    /*
-     * FIXME: This will leak when a failed instruction load or similar
-     * event causes us to longjump out of the translation loop and
-     * hence not clean-up in xtensa_tr_tb_stop
-     */
-    if (dc->config->isa) {
-        dc->insnbuf = xtensa_insnbuf_alloc(dc->config->isa);
-        dc->slotbuf = xtensa_insnbuf_alloc(dc->config->isa);
-    }
     init_sar_tracker(dc);
 }
 
@@ -1272,10 +1262,6 @@ static void xtensa_tr_tb_stop(DisasContextBase *dcbase, CPUState *cpu)
     DisasContext *dc = container_of(dcbase, DisasContext, base);
 
     reset_sar_tracker(dc);
-    if (dc->config->isa) {
-        xtensa_insnbuf_free(dc->config->isa, dc->insnbuf);
-        xtensa_insnbuf_free(dc->config->isa, dc->slotbuf);
-    }
     if (dc->icount) {
         tcg_temp_free(dc->next_icount);
     }