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authorRichard Henderson <rth@twiddle.net>2013-03-12 17:11:40 -0700
committerAurelien Jarno <aurelien@aurel32.net>2013-04-27 01:19:20 +0200
commitfc4d60ee16e9c20404e9970b421ac3e96df4c214 (patch)
tree6cea7ee809f330dbf58e38cdaab0d5107bfd5bde /tcg
parented605126a8d826e60587cc21d9e7b95e8c49b6f6 (diff)
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tcg-arm: Fix local stack frame
We were not allocating TCG_STATIC_CALL_ARGS_SIZE, so this meant that any helper with more than 4 arguments would clobber the saved regs. Realizing that we're supposed to have this memory pre-allocated means we can clean up the tcg_out_arg functions, which were trying to do more stack allocation. Allocate stack memory for the TCG temporaries while we're at it. Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'tcg')
-rw-r--r--tcg/arm/tcg-target.c121
1 files changed, 47 insertions, 74 deletions
diff --git a/tcg/arm/tcg-target.c b/tcg/arm/tcg-target.c
index 94c6ca4..eda6749 100644
--- a/tcg/arm/tcg-target.c
+++ b/tcg/arm/tcg-target.c
@@ -1017,64 +1017,35 @@ static const void * const qemu_st_helpers[4] = {
* argreg is where we want to put this argument, arg is the argument itself.
* Return value is the updated argreg ready for the next call.
* Note that argreg 0..3 is real registers, 4+ on stack.
- * When we reach the first stacked argument, we allocate space for it
- * and the following stacked arguments using "str r8, [sp, #-0x10]!".
- * Following arguments are filled in with "str r8, [sp, #0xNN]".
- * For more than 4 stacked arguments we'd need to know how much
- * space to allocate when we pushed the first stacked argument.
- * We don't need this, so don't implement it (and will assert if you try it.)
*
* We provide routines for arguments which are: immediate, 32 bit
* value in register, 16 and 8 bit values in register (which must be zero
* extended before use) and 64 bit value in a lo:hi register pair.
*/
-#define DEFINE_TCG_OUT_ARG(NAME, ARGPARAM) \
- static TCGReg NAME(TCGContext *s, TCGReg argreg, ARGPARAM) \
- { \
- if (argreg < 4) { \
- TCG_OUT_ARG_GET_ARG(argreg); \
- } else if (argreg == 4) { \
- TCG_OUT_ARG_GET_ARG(TCG_REG_R8); \
- tcg_out32(s, (COND_AL << 28) | 0x052d8010); \
- } else { \
- assert(argreg < 8); \
- TCG_OUT_ARG_GET_ARG(TCG_REG_R8); \
- tcg_out32(s, (COND_AL << 28) | 0x058d8000 | (argreg - 4) * 4); \
- } \
- return argreg + 1; \
- }
-
-#define TCG_OUT_ARG_GET_ARG(A) tcg_out_dat_imm(s, COND_AL, ARITH_MOV, A, 0, arg)
-DEFINE_TCG_OUT_ARG(tcg_out_arg_imm32, uint32_t arg)
-#undef TCG_OUT_ARG_GET_ARG
-#define TCG_OUT_ARG_GET_ARG(A) tcg_out_ext8u(s, COND_AL, A, arg)
-DEFINE_TCG_OUT_ARG(tcg_out_arg_reg8, TCGReg arg)
-#undef TCG_OUT_ARG_GET_ARG
-#define TCG_OUT_ARG_GET_ARG(A) tcg_out_ext16u(s, COND_AL, A, arg)
-DEFINE_TCG_OUT_ARG(tcg_out_arg_reg16, TCGReg arg)
-#undef TCG_OUT_ARG_GET_ARG
-
-/* We don't use the macro for this one to avoid an unnecessary reg-reg
- * move when storing to the stack.
- */
-static TCGReg tcg_out_arg_reg32(TCGContext *s, TCGReg argreg, TCGReg arg)
-{
- if (argreg < 4) {
- tcg_out_mov_reg(s, COND_AL, argreg, arg);
- } else if (argreg == 4) {
- /* str arg, [sp, #-0x10]! */
- tcg_out32(s, (COND_AL << 28) | 0x052d0010 | (arg << 12));
- } else {
- assert(argreg < 8);
- /* str arg, [sp, #0xNN] */
- tcg_out32(s, (COND_AL << 28) | 0x058d0000 |
- (arg << 12) | (argreg - 4) * 4);
- }
- return argreg + 1;
-}
-
-static inline TCGReg tcg_out_arg_reg64(TCGContext *s, TCGReg argreg,
- TCGReg arglo, TCGReg arghi)
+#define DEFINE_TCG_OUT_ARG(NAME, ARGTYPE, MOV_ARG, EXT_ARG) \
+static TCGReg NAME(TCGContext *s, TCGReg argreg, ARGTYPE arg) \
+{ \
+ if (argreg < 4) { \
+ MOV_ARG(s, COND_AL, argreg, arg); \
+ } else { \
+ int ofs = (argreg - 4) * 4; \
+ EXT_ARG; \
+ assert(ofs + 4 <= TCG_STATIC_CALL_ARGS_SIZE); \
+ tcg_out_st32_12(s, COND_AL, arg, TCG_REG_CALL_STACK, ofs); \
+ } \
+ return argreg + 1; \
+}
+
+DEFINE_TCG_OUT_ARG(tcg_out_arg_imm32, uint32_t, tcg_out_movi32,
+ (tcg_out_movi32(s, COND_AL, TCG_REG_R8, arg), arg = TCG_REG_R8))
+DEFINE_TCG_OUT_ARG(tcg_out_arg_reg8, TCGReg, tcg_out_ext8u,
+ (tcg_out_ext8u(s, COND_AL, TCG_REG_R8, arg), arg = TCG_REG_R8))
+DEFINE_TCG_OUT_ARG(tcg_out_arg_reg16, TCGReg, tcg_out_ext16u,
+ (tcg_out_ext16u(s, COND_AL, TCG_REG_R8, arg), arg = TCG_REG_R8))
+DEFINE_TCG_OUT_ARG(tcg_out_arg_reg32, TCGReg, tcg_out_mov_reg, )
+
+static TCGReg tcg_out_arg_reg64(TCGContext *s, TCGReg argreg,
+ TCGReg arglo, TCGReg arghi)
{
/* 64 bit arguments must go in even/odd register pairs
* and in 8-aligned stack slots.
@@ -1086,16 +1057,7 @@ static inline TCGReg tcg_out_arg_reg64(TCGContext *s, TCGReg argreg,
argreg = tcg_out_arg_reg32(s, argreg, arghi);
return argreg;
}
-
-static inline void tcg_out_arg_stacktidy(TCGContext *s, TCGReg argreg)
-{
- /* Output any necessary post-call cleanup of the stack */
- if (argreg > 4) {
- tcg_out_dat_imm(s, COND_AL, ARITH_ADD, TCG_REG_R13, TCG_REG_R13, 0x10);
- }
-}
-
-#endif
+#endif /* SOFTMMU */
#define TLB_SHIFT (CPU_TLB_ENTRY_BITS + CPU_TLB_BITS)
@@ -1226,7 +1188,6 @@ static inline void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args, int opc)
#endif
argreg = tcg_out_arg_imm32(s, argreg, mem_index);
tcg_out_call(s, (tcg_target_long) qemu_ld_helpers[s_bits]);
- tcg_out_arg_stacktidy(s, argreg);
switch (opc) {
case 0 | 4:
@@ -1444,7 +1405,6 @@ static inline void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, int opc)
argreg = tcg_out_arg_imm32(s, argreg, mem_index);
tcg_out_call(s, (tcg_target_long) qemu_st_helpers[s_bits]);
- tcg_out_arg_stacktidy(s, argreg);
reloc_pc24(label_ptr, (tcg_target_long)s->code_ptr);
#else /* !CONFIG_SOFTMMU */
@@ -1884,8 +1844,6 @@ static void tcg_target_init(TCGContext *s)
tcg_regset_set_reg(s->reserved_regs, TCG_REG_PC);
tcg_add_target_add_op_defs(arm_op_defs);
- tcg_set_frame(s, TCG_AREG0, offsetof(CPUArchState, temp_buf),
- CPU_TEMP_BUF_NLONGS * sizeof(long));
}
static inline void tcg_out_ld(TCGContext *s, TCGType type, TCGReg arg,
@@ -1914,18 +1872,33 @@ static inline void tcg_out_movi(TCGContext *s, TCGType type,
static void tcg_target_qemu_prologue(TCGContext *s)
{
- /* Calling convention requires us to save r4-r11 and lr;
- * save also r12 to maintain stack 8-alignment.
- */
+ int frame_size;
+
+ /* Calling convention requires us to save r4-r11 and lr. */
+ /* stmdb sp!, { r4 - r11, lr } */
+ tcg_out32(s, (COND_AL << 28) | 0x092d4ff0);
- /* stmdb sp!, { r4 - r12, lr } */
- tcg_out32(s, (COND_AL << 28) | 0x092d5ff0);
+ /* Allocate the local stack frame. */
+ frame_size = TCG_STATIC_CALL_ARGS_SIZE;
+ frame_size += CPU_TEMP_BUF_NLONGS * sizeof(long);
+ /* We saved an odd number of registers above; keep an 8 aligned stack. */
+ frame_size = ((frame_size + TCG_TARGET_STACK_ALIGN - 1)
+ & -TCG_TARGET_STACK_ALIGN) + 4;
+
+ tcg_out_dat_rI(s, COND_AL, ARITH_SUB, TCG_REG_CALL_STACK,
+ TCG_REG_CALL_STACK, frame_size, 1);
+ tcg_set_frame(s, TCG_REG_CALL_STACK, TCG_STATIC_CALL_ARGS_SIZE,
+ CPU_TEMP_BUF_NLONGS * sizeof(long));
tcg_out_mov(s, TCG_TYPE_PTR, TCG_AREG0, tcg_target_call_iarg_regs[0]);
tcg_out_bx(s, COND_AL, tcg_target_call_iarg_regs[1]);
tb_ret_addr = s->code_ptr;
- /* ldmia sp!, { r4 - r12, pc } */
- tcg_out32(s, (COND_AL << 28) | 0x08bd9ff0);
+ /* Epilogue. We branch here via tb_ret_addr. */
+ tcg_out_dat_rI(s, COND_AL, ARITH_ADD, TCG_REG_CALL_STACK,
+ TCG_REG_CALL_STACK, frame_size, 1);
+
+ /* ldmia sp!, { r4 - r11, pc } */
+ tcg_out32(s, (COND_AL << 28) | 0x08bd8ff0);
}