undefined symbol: __lshrsi3

[chbessonova]

Clang produces calls for functions like __lshrsi3, __lshrhi3 which is supposed to be a part of runtime library, but they are missed in libgcc for msp430 target.
Example,

  1 int i;
  2 unsigned long *x;
  3 
  4 void foo() {
  5   *x = *x >> i;    
  6 }

clang

foo:
	push	 r10
	mov	&x, r10
	mov	0(r10), r12
	mov	2(r10), r13
	mov.b	&i, r14
	call	#__lshrsi3
	mov	r13, 2(r10)
	mov	r12, 0(r10)
	pop	r10
	ret

gcc

foo:
	PUSH	R10
	MOV.W	&x, R10
	MOV.W	@R10, R12
	MOV.W	2(R10), R13
	MOV.W	&i, R14
	CALL	#__mspabi_srll
	MOV.W	R12, @R10
	MOV.W	R13, 2(R10)
	POP	R10
	RET

Added:
Need to add correct lib call lowering for RTLIB::SRL_I32 and other shifts to MSP430ISelLowering.