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author | David Guillen Fandos | 2021-03-05 17:47:20 +0100 |
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committer | David Guillen Fandos | 2021-03-05 17:47:20 +0100 |
commit | d21478e06edb61d2f0565c06fc6665799a6d7e72 (patch) | |
tree | 0de4a2cd1bb233b1c100c204c7afd7e1f8be0564 | |
parent | 7bebd3051c8723f785263f074ac5b180a9cc0852 (diff) | |
download | picogpsp-d21478e06edb61d2f0565c06fc6665799a6d7e72.tar.gz picogpsp-d21478e06edb61d2f0565c06fc6665799a6d7e72.tar.bz2 picogpsp-d21478e06edb61d2f0565c06fc6665799a6d7e72.zip |
ARM dynarec: Do not use the stack at all
Fix a C func call while at it. This is a prerequisite to make the
dynarec re-entrant and get rid of libco
-rw-r--r-- | arm/arm_stub.S | 19 |
1 files changed, 15 insertions, 4 deletions
diff --git a/arm/arm_stub.S b/arm/arm_stub.S index 687aacf..0de4cb4 100644 --- a/arm/arm_stub.S +++ b/arm/arm_stub.S @@ -40,6 +40,8 @@ #define CPU_HALT_STATE (30 * 4) #define CHANGED_PC_STATUS (31 * 4) +#define REG_HOST_SP (32 * 4) + #define reg_a0 r0 #define reg_a1 r1 @@ -141,13 +143,15 @@ @ Align the stack to 64 bits (ABIs that don't require it, still recommend so) #define call_c_saved_regs r2, r3, r12, lr -@ Calls a C function - all caller save registers which are important to the -@ dynarec and to returning from this function are saved. +@ Calls a C function - reloads the stack pointer and saves all caller save +@ registers which are important to the dynarec. #define call_c_function(function) ;\ + ldr sp, [reg_base, #REG_HOST_SP] ;\ stmdb sp!, { call_c_saved_regs } ;\ bl function ;\ ldmia sp!, { call_c_saved_regs } ;\ + ldr sp, =base_reg_area ;\ @ Update the GBA hardware (video, sound, input, etc) @@ -475,7 +479,9 @@ execute_swi_function_builder(div, thumb) .globl _execute_arm_translate execute_arm_translate: _execute_arm_translate: - sub sp, sp, #0x100 @ allocate room for register data + ldr r1, =base_reg_area @ base_reg_area to r1 + str sp, [r1, #REG_HOST_SP] @ store the current sp + ldr sp, =base_reg_area @ reg_base = sp (loading addr) mvn reg_cycles, r0 @ load cycle counter @@ -603,7 +609,7 @@ write_epilogue: store_registers_arm() @ save ARM registers 3: - bl update_gba @ update GBA until CPU isn't halted + call_c_function(update_gba) @ update GBA until CPU isn't halted mvn reg_cycles, r0 @ load new cycle count ldr r0, [reg_base, #REG_PC] @ load new PC @@ -727,3 +733,8 @@ execute_load_builder(u32, 32, ldrne, #0xF0000000) .comm memory_map_read 0x8000 .comm memory_map_write 0x8000 +.data + +base_reg_area: + .space 0x100, 0 + |