OpenE2K/qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity

target-mips: Correct 32-bit address space wrapping

Browse Source 
Make sure the address space is unconditionally wrapped on 32-bit
processors, that is ones that do not implement at least the MIPS III
ISA.

Also make MIPS16 SAVE and RESTORE instructions use address calculation
rather than plain arithmetic operations for stack pointer manipulation
so that their semantics for stack accesses follows the architecture
specification.  That in particular applies to user software run on
64-bit processors with the CP0.Status.UX bit clear where the address
space is wrapped to 32 bits.

Signed-off-by: Maciej W. Rozycki <macro@codesourcery.com>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
This commit is contained in:
Maciej W. Rozycki 2014-11-19 17:29:00 +00:00 committed by Leon Alrae
parent d922445020
commit c48245f0c6
2 changed files with 19 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
target-mips/cpu.h
View File

@ -838,10 +838,12 @@ static inline void compute_hflags(CPUMIPSState *env)
env->hflags |= MIPS_HFLAG_64;
}
if (((env->hflags & MIPS_HFLAG_KSU) == MIPS_HFLAG_UM) &&
!(env->CP0_Status & (1 << CP0St_UX))) {
if (!(env->insn_flags & ISA_MIPS3)) {
env->hflags |= MIPS_HFLAG_AWRAP;
} else if (env->insn_flags & ISA_MIPS32R6) {
} else if (((env->hflags & MIPS_HFLAG_KSU) == MIPS_HFLAG_UM) &&
!(env->CP0_Status & (1 << CP0St_UX))) {
env->hflags |= MIPS_HFLAG_AWRAP;
} else if (env->insn_flags & ISA_MIPS64R6) {
/* Address wrapping for Supervisor and Kernel is specified in R6 */
if ((((env->hflags & MIPS_HFLAG_KSU) == MIPS_HFLAG_SM) &&
!(env->CP0_Status & (1 << CP0St_SX))) ||

19
target-mips/translate.c
View File

@ -10728,6 +10728,7 @@ static void gen_mips16_save (DisasContext *ctx,
{
TCGv t0 = tcg_temp_new();
TCGv t1 = tcg_temp_new();
TCGv t2 = tcg_temp_new();
int args, astatic;
switch (aregs) {
@ -10786,7 +10787,8 @@ static void gen_mips16_save (DisasContext *ctx,
gen_load_gpr(t0, 29);
#define DECR_AND_STORE(reg) do { \
tcg_gen_subi_tl(t0, t0, 4); \
tcg_gen_movi_tl(t2, -4); \
gen_op_addr_add(ctx, t0, t0, t2); \
gen_load_gpr(t1, reg); \
tcg_gen_qemu_st_tl(t1, t0, ctx->mem_idx, MO_TEUL); \
} while (0)
@ -10870,9 +10872,11 @@ static void gen_mips16_save (DisasContext *ctx,
}
#undef DECR_AND_STORE
tcg_gen_subi_tl(cpu_gpr[29], cpu_gpr[29], framesize);
tcg_gen_movi_tl(t2, -framesize);
gen_op_addr_add(ctx, cpu_gpr[29], cpu_gpr[29], t2);
tcg_temp_free(t0);
tcg_temp_free(t1);
tcg_temp_free(t2);
}
static void gen_mips16_restore (DisasContext *ctx,
@ -10883,11 +10887,14 @@ static void gen_mips16_restore (DisasContext *ctx,
int astatic;
TCGv t0 = tcg_temp_new();
TCGv t1 = tcg_temp_new();
TCGv t2 = tcg_temp_new();
tcg_gen_addi_tl(t0, cpu_gpr[29], framesize);
tcg_gen_movi_tl(t2, framesize);
gen_op_addr_add(ctx, t0, cpu_gpr[29], t2);
#define DECR_AND_LOAD(reg) do { \
tcg_gen_subi_tl(t0, t0, 4); \
tcg_gen_movi_tl(t2, -4); \
gen_op_addr_add(ctx, t0, t0, t2); \
tcg_gen_qemu_ld_tl(t1, t0, ctx->mem_idx, MO_TESL); \
gen_store_gpr(t1, reg); \
} while (0)
@ -10971,9 +10978,11 @@ static void gen_mips16_restore (DisasContext *ctx,
}
#undef DECR_AND_LOAD
tcg_gen_addi_tl(cpu_gpr[29], cpu_gpr[29], framesize);
tcg_gen_movi_tl(t2, framesize);
gen_op_addr_add(ctx, cpu_gpr[29], cpu_gpr[29], t2);
tcg_temp_free(t0);
tcg_temp_free(t1);
tcg_temp_free(t2);
}
static void gen_addiupc (DisasContext *ctx, int rx, int imm,