[SubZero] Handle relocatable constants for MIPS

tests_lit/llvm2ice_tests/arith.ll

 ; Assembly test for simple arithmetic operations.
 
 ; RUN: %if --need=target_X8632 --command %p2i --filetype=obj --disassemble \
 ; RUN:   --target x8632 -i %s --args -O2 \
 ; RUN:   | %if --need=target_X8632 --command FileCheck %s
 
 ; RUN: %if --need=target_ARM32 \
 ; RUN:   --command %p2i --filetype=obj --disassemble --target arm32 \
 ; RUN:   -i %s --args -O2 \
 ; RUN:   | %if --need=target_ARM32 \
@@ skipping 258 matching lines @@
 
 define internal i32 @ShlReloc(i32 %a) {
 entry:
   %opnd = ptrtoint [4 x i8]* @G to i32
   %result = shl i32 %a, %opnd
   ret i32 %result
 }
 ; CHECK-LABEL: ShlReloc
 ; CHECK: shl {{.*}},cl
 
+; MIPS32-LABEL: ShlReloc
+; MIPS32: lui [[REG:.*]],{{.*}} R_MIPS_HI16 G
+; MIPS32: addiu [[REG]],[[REG]],{{.*}} R_MIPS_LO16 G
+; MIPS32: sllv {{.*}},{{.*}},[[REG]]
+
 define internal i32 @LshrReloc(i32 %a) {
 entry:
   %opnd = ptrtoint [4 x i8]* @G to i32
   %result = lshr i32 %a, %opnd
   ret i32 %result
 }
 ; CHECK-LABEL: LshrReloc
 ; CHECK: shr {{.*}},cl
 
+; MIPS32-LABEL: LshrReloc
+; MIPS32: lui [[REG:.*]],{{.*}} R_MIPS_HI16 G
+; MIPS32: addiu [[REG]],[[REG]],{{.*}} R_MIPS_LO16 G
+; MIPS32: srlv {{.*}},{{.*}},[[REG]]
+
 define internal i32 @AshrReloc(i32 %a) {
 entry:
   %opnd = ptrtoint [4 x i8]* @G to i32
   %result = ashr i32 %a, %opnd
   ret i32 %result
 }
 ; CHECK-LABEL: AshrReloc
 ; CHECK: sar {{.*}},cl
+
+; MIPS32-LABEL: AshrReloc
+; MIPS32: lui [[REG:.*]],{{.*}} R_MIPS_HI16 G
+; MIPS32: addiu [[REG]],[[REG]],{{.*}} R_MIPS_LO16 G
+; MIPS32: srav {{.*}},{{.*}},[[REG]]