4.3 Use of Machine Registers and Stack Frame Slots for x86_64 (non-Windows)

%raxgpr(0)val, arg0
%rcxgpr(1)cp
%rdxgpr(2)s
%rbxgpr(3)w
%rspgpr(4)SP
%rbpgpr(5)a
%rsigpr(6)h
%rdigpr(7)e
%r8gpr(8)b
%r9gpr(9)tr
%r10gpr(10)arg1
%r11gpr(11)arg2
%r12gpr(12)x(0)
%r13gpr(13)x(1)
%r14gpr(14)x(2)
%r15gpr(15)x(3)
0(%rsp)%rbx callee save
8(%rsp)%rbp callee save
16(%rsp)%r12 callee save
24(%rsp)%r13 callee save
32(%rsp)%r14 callee save
40(%rsp)%r15 callee save
48(%rsp)ac0
56(%rsp)ac1
64(%rsp)arg0 spill slot
72(%rsp)pad
80(%rsp)ret address

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