From e89b28a63501c0ad6d2501fe851d0c5202055e70 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 20 Oct 2017 12:08:19 -0700 Subject: tcg: Use offsets not indices for TCGv_* MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Emilio G. Cota Signed-off-by: Richard Henderson --- tcg/tcg.h | 64 ++++++++++++++++++++++++++++++++------------------------------- 1 file changed, 33 insertions(+), 31 deletions(-) diff --git a/tcg/tcg.h b/tcg/tcg.h index 8f692bc6cf..c85786fb47 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 -- cgit v1.2.3