target/hppa: Implement prctl_unalign_sigbus

Leave TARGET_ALIGNED_ONLY set, but use the new CPUState
flag to set MO_UNALN for the instructions that the kernel
handles in the unaligned trap.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20211227150127.2659293-6-richard.henderson@linaro.org>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>

linux-user/hppa/target_prctl.h

@@ -1 +1 @@
-/* No special prctl support required. */
+#include "../generic/target_prctl_unalign.h"

target/hppa/cpu.h

@@ -259,12 +259,14 @@ static inline target_ulong hppa_form_gva(CPUHPPAState *env, uint64_t spc,
     return hppa_form_gva_psw(env->psw, spc, off);
 }
 
-/* Since PSW_{I,CB} will never need to be in tb->flags, reuse them.
+/*
+ * Since PSW_{I,CB} will never need to be in tb->flags, reuse them.
  * TB_FLAG_SR_SAME indicates that SR4 through SR7 all contain the
  * same value.
  */
 #define TB_FLAG_SR_SAME     PSW_I
 #define TB_FLAG_PRIV_SHIFT  8
+#define TB_FLAG_UNALIGN     0x400
 
 static inline void cpu_get_tb_cpu_state(CPUHPPAState *env, target_ulong *pc,
                                         target_ulong *cs_base,
@@ -279,6 +281,7 @@ static inline void cpu_get_tb_cpu_state(CPUHPPAState *env, target_ulong *pc,
 #ifdef CONFIG_USER_ONLY
     *pc = env->iaoq_f & -4;
     *cs_base = env->iaoq_b & -4;
+    flags |= TB_FLAG_UNALIGN * !env_cpu(env)->prctl_unalign_sigbus;
 #else
     /* ??? E, T, H, L, B, P bits need to be here, when implemented.  */
     flags |= env->psw & (PSW_W | PSW_C | PSW_D);

target/hppa/translate.c

@@ -274,8 +274,18 @@ typedef struct DisasContext {
     int mmu_idx;
     int privilege;
     bool psw_n_nonzero;
+
+#ifdef CONFIG_USER_ONLY
+    MemOp unalign;
+#endif
 } DisasContext;
 
+#ifdef CONFIG_USER_ONLY
+#define UNALIGN(C)  (C)->unalign
+#else
+#define UNALIGN(C)  0
+#endif
+
 /* Note that ssm/rsm instructions number PSW_W and PSW_E differently.  */
 static int expand_sm_imm(DisasContext *ctx, int val)
 {
@@ -1475,7 +1485,7 @@ static void do_load_32(DisasContext *ctx, TCGv_i32 dest, unsigned rb,
 
     form_gva(ctx, &addr, &ofs, rb, rx, scale, disp, sp, modify,
              ctx->mmu_idx == MMU_PHYS_IDX);
-    tcg_gen_qemu_ld_reg(dest, addr, ctx->mmu_idx, mop);
+    tcg_gen_qemu_ld_reg(dest, addr, ctx->mmu_idx, mop | UNALIGN(ctx));
     if (modify) {
         save_gpr(ctx, rb, ofs);
     }
@@ -1493,7 +1503,7 @@ static void do_load_64(DisasContext *ctx, TCGv_i64 dest, unsigned rb,
 
     form_gva(ctx, &addr, &ofs, rb, rx, scale, disp, sp, modify,
              ctx->mmu_idx == MMU_PHYS_IDX);
-    tcg_gen_qemu_ld_i64(dest, addr, ctx->mmu_idx, mop);
+    tcg_gen_qemu_ld_i64(dest, addr, ctx->mmu_idx, mop | UNALIGN(ctx));
     if (modify) {
         save_gpr(ctx, rb, ofs);
     }
@@ -1511,7 +1521,7 @@ static void do_store_32(DisasContext *ctx, TCGv_i32 src, unsigned rb,
 
     form_gva(ctx, &addr, &ofs, rb, rx, scale, disp, sp, modify,
              ctx->mmu_idx == MMU_PHYS_IDX);
-    tcg_gen_qemu_st_i32(src, addr, ctx->mmu_idx, mop);
+    tcg_gen_qemu_st_i32(src, addr, ctx->mmu_idx, mop | UNALIGN(ctx));
     if (modify) {
         save_gpr(ctx, rb, ofs);
     }
@@ -1529,7 +1539,7 @@ static void do_store_64(DisasContext *ctx, TCGv_i64 src, unsigned rb,
 
     form_gva(ctx, &addr, &ofs, rb, rx, scale, disp, sp, modify,
              ctx->mmu_idx == MMU_PHYS_IDX);
-    tcg_gen_qemu_st_i64(src, addr, ctx->mmu_idx, mop);
+    tcg_gen_qemu_st_i64(src, addr, ctx->mmu_idx, mop | UNALIGN(ctx));
     if (modify) {
         save_gpr(ctx, rb, ofs);
     }
@@ -4107,6 +4117,7 @@ static void hppa_tr_init_disas_context(DisasContextBase *dcbase, CPUState *cs)
     ctx->mmu_idx = MMU_USER_IDX;
     ctx->iaoq_f = ctx->base.pc_first | MMU_USER_IDX;
     ctx->iaoq_b = ctx->base.tb->cs_base | MMU_USER_IDX;
+    ctx->unalign = (ctx->tb_flags & TB_FLAG_UNALIGN ? MO_UNALN : MO_ALIGN);
 #else
     ctx->privilege = (ctx->tb_flags >> TB_FLAG_PRIV_SHIFT) & 3;
     ctx->mmu_idx = (ctx->tb_flags & PSW_D ? ctx->privilege : MMU_PHYS_IDX);