[SubZero] Implement GP to/from FP moves for MIPS

tests_lit/llvm2ice_tests/fp.load_store.ll

 ; This tries to be a comprehensive test of f32 and f64 compare operations.
 ; The CHECK lines are only checking for basic instruction patterns
 ; that should be present regardless of the optimization level, so
 ; there are no special OPTM1 match lines.
 
 ; RUN: %p2i --filetype=obj --disassemble -i %s --args -O2 | FileCheck %s
 ; RUN: %p2i --filetype=obj --disassemble -i %s --args -Om1 | FileCheck %s
 
 ; RUN: %if --need=target_MIPS32 --need=allow_dump \
 ; RUN:   --command %p2i --filetype=asm --assemble \
 ; RUN:   --disassemble --target mips32 -i %s --args -Om1 --skip-unimplemented \
 ; RUN:   -allow-externally-defined-symbols \
 ; RUN:   | %if --need=target_MIPS32 --need=allow_dump \
 ; RUN:   --command FileCheck --check-prefix MIPS32 %s
 
+; RUN: %if --need=target_MIPS32 --need=allow_dump \
+; RUN:   --command %p2i --filetype=asm --assemble \
+; RUN:   --disassemble --target mips32 -i %s --args -O2 --skip-unimplemented \
+; RUN:   -allow-externally-defined-symbols \
+; RUN:   | %if --need=target_MIPS32 --need=allow_dump \
+; RUN:   --command FileCheck --check-prefix MIPS32O2 %s
+
 define internal float @loadFloat(i32 %a) {
 entry:
   %__1 = inttoptr i32 %a to float*
   %v0 = load float, float* %__1, align 4
   ret float %v0
 }
 ; CHECK-LABEL: loadFloat
 ; CHECK: movss
 ; CHECK: fld
 
 ; MIPS32-LABEL: loadFloat
 ; MIPS32: lwc1 $f{{.*}},0{{.*}}
+; MIPS32O2-LABEL: loadFloat
+; MIPS32O2: lwc1 $f{{.*}},0{{.*}}
 
 define internal double @loadDouble(i32 %a) {
 entry:
   %__1 = inttoptr i32 %a to double*
   %v0 = load double, double* %__1, align 8
   ret double %v0
 }
 ; CHECK-LABEL: loadDouble
 ; CHECK: movsd
 ; CHECK: fld
 
 ; MIPS32-LABEL: loadDouble
 ; MIPS32: ldc1 $f{{.*}},0{{.*}}
+; MIPS32O2-LABEL: loadDouble
+; MIPS32O2: ldc1 $f{{.*}},0{{.*}}
 
 define internal void @storeFloat(i32 %a, float %value) {
 entry:
   %__2 = inttoptr i32 %a to float*
   store float %value, float* %__2, align 4
   ret void
 }
 ; CHECK-LABEL: storeFloat
 ; CHECK: movss
 ; CHECK: movss
 
 ; MIPS32-LABEL: storeFloat
 ; MIPS32: swc1 $f{{.*}},0{{.*}}
+; MIPS32O2-LABEL: storeFloat
+; MIPS32O2: mtc1 a1,$f{{.*}}
+; MIPS32O2: swc1 $f{{.*}},0(a0)
 
 define internal void @storeDouble(i32 %a, double %value) {
 entry:
   %__2 = inttoptr i32 %a to double*
   store double %value, double* %__2, align 8
   ret void
 }
 ; CHECK-LABEL: storeDouble
 ; CHECK: movsd
 ; CHECK: movsd
 
 ; MIPS32-LABEL: storeDouble
 ; MIPS32: ldc1 $f{{.*}},4{{.*}}
 ; MIPS32: sdc1 $f{{.*}},0{{.*}}
+; MIPS32O2-LABEL: storeDouble
+; MIPS32O2: mtc1 a3,$f{{.*}}
+; MIPS32O2: mtc1 a2,$f{{.*}}
+; MIPS32O2: sdc1 $f{{.*}},0(a0)
 
 define internal void @storeFloatConst(i32 %a) {
 entry:
   %a.asptr = inttoptr i32 %a to float*
   store float 0x3FF3AE1480000000, float* %a.asptr, align 4
   ret void
 }
 ; CHECK-LABEL: storeFloatConst
 ; CHECK: movss
 ; CHECK: movss
 
 ; MIPS32-LABEL: storeFloatConst
 ; MIPS32: lui {{.*}},{{.*}}
 ; MIPS32: lwc1 $f{{.*}},{{.*}}
 ; MIPS32: swc1 $f{{.*}},0{{.*}}
+; MIPS32O2-LABEL: storeFloatConst
+; MIPS32O2: lui {{.*}},{{.*}}
+; MIPS32O2: lwc1 $f{{.*}},{{.*}}
+; MIPS32O2: swc1 $f{{.*}},0{{.*}}
 
 define internal void @storeDoubleConst(i32 %a) {
 entry:
   %a.asptr = inttoptr i32 %a to double*
   store double 1.230000e+00, double* %a.asptr, align 8
   ret void
 }
 ; CHECK-LABEL: storeDoubleConst
 ; CHECK: movsd
 ; CHECK: movsd
 
 ; MIPS32-LABEL: storeDoubleConst
 ; MIPS32: lui {{.*}},{{.*}}
 ; MIPS32: ldc1 $f{{.*}},{{.*}}
 ; MIPS32: sdc1 $f{{.*}},0{{.*}}
+; MIPS32O2-LABEL: storeDoubleConst
+; MIPS32O2: lui {{.*}},{{.*}}
+; MIPS32O2: ldc1 $f{{.*}},{{.*}}
+; MIPS32O2: sdc1 $f{{.*}},0{{.*}}