s390x: Add LER and LEZR simulator implementation

Change-Id: I771d3db6510146b043c9dd0a3bae8a9a67b21176
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2552927Reviewed-by: Milad Fa <mfarazma@redhat.com>
Commit-Queue: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/master@{#71323}

src/execution/s390/simulator-s390.cc

@@ -4959,9 +4959,11 @@ EVALUATE(CDR) {
 }
 
 EVALUATE(LER) {
-  UNIMPLEMENTED();
-  USE(instr);
-  return 0;
+  DCHECK_OPCODE(LER);
+  DECODE_RR_INSTRUCTION(r1, r2);
+  int64_t r2_val = get_f_register(r2);
+  set_d_register(r1, r2_val);
+  return length;
 }
 
 EVALUATE(STH) {
@@ -7288,9 +7290,10 @@ EVALUATE(LCDFR) {
 }
 
 EVALUATE(LZER) {
-  UNIMPLEMENTED();
-  USE(instr);
-  return 0;
+  DCHECK_OPCODE(LZER);
+  DECODE_RRE_INSTRUCTION_NO_R2(r1);
+  set_d_register_from_float32(r1, 0.0);
+  return length;
 }
 
 EVALUATE(LZDR) {

src/execution/s390/simulator-s390.h

@@ -157,6 +157,13 @@ class Simulator : public SimulatorBase {
     return get_simd_register_by_lane<int64_t>(dreg, 0);
   }
 
+  int64_t get_f_register(int dreg) {
+    DCHECK(dreg >= 0 && dreg < kNumFPRs);
+    int64_t d_val = get_simd_register_by_lane<int64_t>(dreg, 0);
+    int64_t f_val = d_val >> 32;
+    return f_val << 32;
+  }
+
   void set_d_register_from_float32(int dreg, const float f) {
     DCHECK(dreg >= 0 && dreg < kNumFPRs);