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authorRichard Henderson <richard.henderson@linaro.org>2017-10-20 12:08:19 -0700
committerRichard Henderson <richard.henderson@linaro.org>2017-10-24 13:53:36 -0700
commite89b28a63501c0ad6d2501fe851d0c5202055e70 (patch)
tree8e4859ec99e87c099d3808bfd122e7ed9b2aef13 /tcg
parent55c3ceef61fcf06fc98ddc752b7cce788ce7680b (diff)
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tcg: Use offsets not indices for TCGv_*
Using the offset of a temporary, relative to TCGContext, rather than its index means that we don't use 0. That leaves offset 0 free for a NULL representation without having to leave index 0 unused. Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Reviewed-by: Emilio G. Cota <cota@braap.org> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'tcg')
-rw-r--r--tcg/tcg.h64
1 files changed, 33 insertions, 31 deletions
diff --git a/tcg/tcg.h b/tcg/tcg.h
index 8f692bc..c85786f 100644
--- a/tcg/tcg.h
+++ b/tcg/tcg.h
@@ -428,14 +428,14 @@ typedef TCGv_ptr TCGv_env;
#error Unhandled TARGET_LONG_BITS value
#endif
-/* Dummy definition to avoid compiler warnings. */
-#define TCGV_UNUSED_I32(x) (x = (TCGv_i32)-1)
-#define TCGV_UNUSED_I64(x) (x = (TCGv_i64)-1)
-#define TCGV_UNUSED_PTR(x) (x = (TCGv_ptr)-1)
+/* See the comment before tcgv_i32_temp. */
+#define TCGV_UNUSED_I32(x) (x = (TCGv_i32)NULL)
+#define TCGV_UNUSED_I64(x) (x = (TCGv_i64)NULL)
+#define TCGV_UNUSED_PTR(x) (x = (TCGv_ptr)NULL)
-#define TCGV_IS_UNUSED_I32(x) ((x) == (TCGv_i32)-1)
-#define TCGV_IS_UNUSED_I64(x) ((x) == (TCGv_i64)-1)
-#define TCGV_IS_UNUSED_PTR(x) ((x) == (TCGv_ptr)-1)
+#define TCGV_IS_UNUSED_I32(x) ((x) == (TCGv_i32)NULL)
+#define TCGV_IS_UNUSED_I64(x) ((x) == (TCGv_i64)NULL)
+#define TCGV_IS_UNUSED_PTR(x) ((x) == (TCGv_ptr)NULL)
/* call flags */
/* Helper does not read globals (either directly or through an exception). It
@@ -453,8 +453,8 @@ typedef TCGv_ptr TCGv_env;
#define TCG_CALL_NO_RWG_SE (TCG_CALL_NO_RWG | TCG_CALL_NO_SE)
#define TCG_CALL_NO_WG_SE (TCG_CALL_NO_WG | TCG_CALL_NO_SE)
-/* used to align parameters */
-#define TCG_CALL_DUMMY_ARG ((TCGArg)(-1))
+/* Used to align parameters. See the comment before tcgv_i32_temp. */
+#define TCG_CALL_DUMMY_ARG ((TCGArg)0)
/* Conditions. Note that these are laid out for easy manipulation by
the functions below:
@@ -701,62 +701,64 @@ static inline size_t temp_idx(TCGTemp *ts)
static inline TCGArg temp_arg(TCGTemp *ts)
{
- return temp_idx(ts);
+ return (uintptr_t)ts;
}
static inline TCGTemp *arg_temp(TCGArg a)
{
- return a == TCG_CALL_DUMMY_ARG ? NULL : &tcg_ctx.temps[a];
+ return (TCGTemp *)(uintptr_t)a;
}
-static inline size_t arg_index(TCGArg a)
+/* Using the offset of a temporary, relative to TCGContext, rather than
+ its index means that we don't use 0. That leaves offset 0 free for
+ a NULL representation without having to leave index 0 unused. */
+static inline TCGTemp *tcgv_i32_temp(TCGv_i32 v)
{
- return a;
-}
-
-static inline TCGArg tcgv_i32_arg(TCGv_i32 t)
-{
- return (intptr_t)t;
+ uintptr_t o = (uintptr_t)v;
+ TCGTemp *t = (void *)&tcg_ctx + o;
+ tcg_debug_assert(offsetof(TCGContext, temps[temp_idx(t)]) == o);
+ return t;
}
-static inline TCGArg tcgv_i64_arg(TCGv_i64 t)
+static inline TCGTemp *tcgv_i64_temp(TCGv_i64 v)
{
- return (intptr_t)t;
+ return tcgv_i32_temp((TCGv_i32)v);
}
-static inline TCGArg tcgv_ptr_arg(TCGv_ptr t)
+static inline TCGTemp *tcgv_ptr_temp(TCGv_ptr v)
{
- return (intptr_t)t;
+ return tcgv_i32_temp((TCGv_i32)v);
}
-static inline TCGTemp *tcgv_i32_temp(TCGv_i32 t)
+static inline TCGArg tcgv_i32_arg(TCGv_i32 v)
{
- return arg_temp(tcgv_i32_arg(t));
+ return temp_arg(tcgv_i32_temp(v));
}
-static inline TCGTemp *tcgv_i64_temp(TCGv_i64 t)
+static inline TCGArg tcgv_i64_arg(TCGv_i64 v)
{
- return arg_temp(tcgv_i64_arg(t));
+ return temp_arg(tcgv_i64_temp(v));
}
-static inline TCGTemp *tcgv_ptr_temp(TCGv_ptr t)
+static inline TCGArg tcgv_ptr_arg(TCGv_ptr v)
{
- return arg_temp(tcgv_ptr_arg(t));
+ return temp_arg(tcgv_ptr_temp(v));
}
static inline TCGv_i32 temp_tcgv_i32(TCGTemp *t)
{
- return (TCGv_i32)temp_idx(t);
+ (void)temp_idx(t); /* trigger embedded assert */
+ return (TCGv_i32)((void *)t - (void *)&tcg_ctx);
}
static inline TCGv_i64 temp_tcgv_i64(TCGTemp *t)
{
- return (TCGv_i64)temp_idx(t);
+ return (TCGv_i64)temp_tcgv_i32(t);
}
static inline TCGv_ptr temp_tcgv_ptr(TCGTemp *t)
{
- return (TCGv_ptr)temp_idx(t);
+ return (TCGv_ptr)temp_tcgv_i32(t);
}
#if TCG_TARGET_REG_BITS == 32