[PATCH 24/89] linux-user/arm: Create init_main_thread

[Richard Henderson <richard.henderson@linaro.org>]

Merge init_thread and target_cpu_copy_regs.
There's no point going through a target_pt_regs intermediate.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 linux-user/arm/cpu_loop.c | 53 ++++++++++++++++++++++++++++++++-------
 linux-user/elfload.c      | 41 +-----------------------------
 2 files changed, 45 insertions(+), 49 deletions(-)

diff --git a/linux-user/arm/cpu_loop.c b/linux-user/arm/cpu_loop.c
index 1f3bb96484..8974b35e8d 100644
--- a/linux-user/arm/cpu_loop.c
+++ b/linux-user/arm/cpu_loop.c
@@ -480,19 +480,54 @@ void cpu_loop(CPUARMState *env)
     }
 }
 
-void target_cpu_copy_regs(CPUArchState *env, target_pt_regs *regs)
+void init_main_thread(CPUState *cs, struct image_info *info)
 {
-    cpsr_write(env, regs->uregs[16], CPSR_USER | CPSR_EXEC,
-               CPSRWriteByInstr);
-    for (int i = 0; i < 16; i++) {
-        env->regs[i] = regs->uregs[i];
+    CPUARMState *env = cpu_env(cs);
+    abi_ptr stack = info->start_stack;
+    abi_ptr entry = info->entry;
+
+    cpsr_write(env, ARM_CPU_MODE_USR | (entry & 1 ? CPSR_T : 0),
+               CPSR_USER | CPSR_EXEC, CPSRWriteByInstr);
+
+    env->regs[15] = entry & 0xfffffffe;
+    env->regs[13] = stack;
+
+    /* FIXME - what to for failure of get_user()? */
+    /* FIXME - a modern kernel does not do this? */
+    get_user_ual(env->regs[2], stack + 8); /* envp */
+    get_user_ual(env->regs[1], stack + 4); /* envp */
+
+    /*
+     * Per the SVR4 ABI, r0 contains a pointer to a function to be
+     * registered with atexit.  A value of 0 means we have no such handler.
+     */
+    env->regs[0] = 0;
+
+    /* For uClinux PIC binaries.  */
+    /* XXX: Linux does this only on ARM with no MMU (do we care ?) */
+    env->regs[10] = info->start_data;
+
+    /* Support ARM FDPIC.  */
+    if (info_is_fdpic(info)) {
+        /*
+         * As described in the ABI document, r7 points to the loadmap info
+         * prepared by the kernel. If an interpreter is needed, r8 points
+         * to the interpreter loadmap and r9 points to the interpreter
+         * PT_DYNAMIC info. If no interpreter is needed, r8 is zero, and
+         * r9 points to the main program PT_DYNAMIC info.
+         */
+        env->regs[7] = info->loadmap_addr;
+        if (info->interpreter_loadmap_addr) {
+            /* Executable is dynamically loaded.  */
+            env->regs[8] = info->interpreter_loadmap_addr;
+            env->regs[9] = info->interpreter_pt_dynamic_addr;
+        } else {
+            env->regs[8] = 0;
+            env->regs[9] = info->pt_dynamic_addr;
+        }
     }
 
     if (TARGET_BIG_ENDIAN) {
-        CPUState *cpu = env_cpu(env);
-        TaskState *ts = get_task_state(cpu);
-        struct image_info *info = ts->info;
-
         /* Enable BE8.  */
         if (EF_ARM_EABI_VERSION(info->elf_flags) >= EF_ARM_EABI_VER4
             && (info->elf_flags & EF_ARM_BE8)) {
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 553d632d46..a9a1d7222a 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -299,46 +299,7 @@ static void elf_core_copy_regs(target_elf_gregset_t *regs, const CPUX86State *en
 #define ELF_CLASS       ELFCLASS32
 #define EXSTACK_DEFAULT true
 
-static inline void init_thread(struct target_pt_regs *regs,
-                               struct image_info *infop)
-{
-    abi_long stack = infop->start_stack;
-    memset(regs, 0, sizeof(*regs));
-
-    regs->uregs[16] = ARM_CPU_MODE_USR;
-    if (infop->entry & 1) {
-        regs->uregs[16] |= CPSR_T;
-    }
-    regs->uregs[15] = infop->entry & 0xfffffffe;
-    regs->uregs[13] = infop->start_stack;
-    /* FIXME - what to for failure of get_user()? */
-    get_user_ual(regs->uregs[2], stack + 8); /* envp */
-    get_user_ual(regs->uregs[1], stack + 4); /* envp */
-    /* XXX: it seems that r0 is zeroed after ! */
-    regs->uregs[0] = 0;
-    /* For uClinux PIC binaries.  */
-    /* XXX: Linux does this only on ARM with no MMU (do we care ?) */
-    regs->uregs[10] = infop->start_data;
-
-    /* Support ARM FDPIC.  */
-    if (info_is_fdpic(infop)) {
-        /* As described in the ABI document, r7 points to the loadmap info
-         * prepared by the kernel. If an interpreter is needed, r8 points
-         * to the interpreter loadmap and r9 points to the interpreter
-         * PT_DYNAMIC info. If no interpreter is needed, r8 is zero, and
-         * r9 points to the main program PT_DYNAMIC info.
-         */
-        regs->uregs[7] = infop->loadmap_addr;
-        if (infop->interpreter_loadmap_addr) {
-            /* Executable is dynamically loaded.  */
-            regs->uregs[8] = infop->interpreter_loadmap_addr;
-            regs->uregs[9] = infop->interpreter_pt_dynamic_addr;
-        } else {
-            regs->uregs[8] = 0;
-            regs->uregs[9] = infop->pt_dynamic_addr;
-        }
-    }
-}
+#define HAVE_INIT_MAIN_THREAD
 
 #define ELF_NREG    18
 typedef target_elf_greg_t  target_elf_gregset_t[ELF_NREG];
-- 
2.43.0