py/asmarm: Simplify asm_arm_bl_ind to only load via index, not literal.

The maximum index into mp_fun_table is currently less than 1024 and should
stay that way to keep things efficient for all architectures, so there is
no need to handle loading the pointer directly via a literal in this
function.

3 files changed, 8 insertions, 16 deletions

diff --git a/py/asmarm.c b/py/asmarm.c
index fefe5b15c..3610f838e 100644
--- a/py/asmarm.c
+++ b/py/asmarm.c
@@ -362,19 +362,11 @@ void asm_arm_b_label(asm_arm_t *as, uint label) {
     asm_arm_bcc_label(as, ASM_ARM_CC_AL, label);
 }
 
-void asm_arm_bl_ind(asm_arm_t *as, void *fun_ptr, uint fun_id, uint reg_temp) {
-    // If the table offset fits into the ldr instruction
-    if (fun_id < (0x1000 / 4)) {
-        emit_al(as, asm_arm_op_mov_reg(ASM_ARM_REG_LR, ASM_ARM_REG_PC)); // mov lr, pc
-        emit_al(as, 0x597f000 | (fun_id << 2)); // ldr pc, [r7, #fun_id*4]
-        return;
-    }
-
-    emit_al(as, 0x59f0004 | (reg_temp << 12)); // ldr rd, [pc, #4]
-    // Set lr after fun_ptr
-    emit_al(as, asm_arm_op_add_imm(ASM_ARM_REG_LR, ASM_ARM_REG_PC, 4)); // add lr, pc, #4
-    emit_al(as, asm_arm_op_mov_reg(ASM_ARM_REG_PC, reg_temp)); // mov pc, reg_temp
-    emit(as, (uint) fun_ptr);
+void asm_arm_bl_ind(asm_arm_t *as, uint fun_id, uint reg_temp) {
+    // The table offset should fit into the ldr instruction
+    assert(fun_id < (0x1000 / 4));
+    emit_al(as, asm_arm_op_mov_reg(ASM_ARM_REG_LR, ASM_ARM_REG_PC)); // mov lr, pc
+    emit_al(as, 0x597f000 | (fun_id << 2)); // ldr pc, [r7, #fun_id*4]
 }
 
 void asm_arm_bx_reg(asm_arm_t *as, uint reg_src) {
diff --git a/py/asmarm.h b/py/asmarm.h
index 3ee633c22..219f88c53 100644
--- a/py/asmarm.h
+++ b/py/asmarm.h
@@ -121,7 +121,7 @@ void asm_arm_pop(asm_arm_t *as, uint reglist);
 // control flow
 void asm_arm_bcc_label(asm_arm_t *as, int cond, uint label);
 void asm_arm_b_label(asm_arm_t *as, uint label);
-void asm_arm_bl_ind(asm_arm_t *as, void *fun_ptr, uint fun_id, uint reg_temp);
+void asm_arm_bl_ind(asm_arm_t *as, uint fun_id, uint reg_temp);
 void asm_arm_bx_reg(asm_arm_t *as, uint reg_src);
 
 // Holds a pointer to mp_fun_table
@@ -174,7 +174,7 @@ void asm_arm_bx_reg(asm_arm_t *as, uint reg_src);
         asm_arm_bcc_label(as, ASM_ARM_CC_EQ, label); \
     } while (0)
 #define ASM_JUMP_REG(as, reg) asm_arm_bx_reg((as), (reg))
-#define ASM_CALL_IND(as, ptr, idx) asm_arm_bl_ind(as, ptr, idx, ASM_ARM_REG_R3)
+#define ASM_CALL_IND(as, ptr, idx) asm_arm_bl_ind(as, idx, ASM_ARM_REG_R3)
 
 #define ASM_MOV_LOCAL_REG(as, local_num, reg_src) asm_arm_mov_local_reg((as), (local_num), (reg_src))
 #define ASM_MOV_REG_IMM(as, reg_dest, imm) asm_arm_mov_reg_i32((as), (reg_dest), (imm))
diff --git a/py/emitnative.c b/py/emitnative.c
index 26af7f947..300f84c31 100644
--- a/py/emitnative.c
+++ b/py/emitnative.c
@@ -489,7 +489,7 @@ STATIC void emit_native_start_pass(emit_t *emit, pass_kind_t pass, scope_t *scop
             #if N_THUMB
             asm_thumb_bl_ind(emit->as, mp_fun_table[MP_F_SETUP_CODE_STATE], MP_F_SETUP_CODE_STATE, ASM_THUMB_REG_R4);
             #elif N_ARM
-            asm_arm_bl_ind(emit->as, mp_fun_table[MP_F_SETUP_CODE_STATE], MP_F_SETUP_CODE_STATE, ASM_ARM_REG_R4);
+            asm_arm_bl_ind(emit->as, MP_F_SETUP_CODE_STATE, ASM_ARM_REG_R4);
             #else
             ASM_CALL_IND(emit->as, mp_fun_table[MP_F_SETUP_CODE_STATE], MP_F_SETUP_CODE_STATE);
             #endif