MIPS[64]R6 Fix test-run-wasm-simd/RunWasm_S32x4Dup_compiled

Bug: 
Change-Id: If922715b071276613fd27b6cc7f5326fdc9a37db
Reviewed-on: https://chromium-review.googlesource.com/753091
Commit-Queue: Ivica Bogosavljevic <ivica.bogosavljevic@imgtec.com>
Reviewed-by: Ivica Bogosavljevic <ivica.bogosavljevic@imgtec.com>
Cr-Commit-Position: refs/heads/master@{#49108}

src/compiler/mips/code-generator-mips.cc

@@ -2573,9 +2573,26 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
 
       if (src0 == src1) {
         // Unary S32x4 shuffles are handled with shf.w instruction
+        unsigned lane = shuffle & 0xff;
+        if (FLAG_debug_code) {
+          // range of all four lanes, for unary instruction,
+          // should belong to the same range, which can be one of these:
+          // [0, 3] or [4, 7]
+          if (lane >= 4) {
+            int32_t shuffle_helper = shuffle;
+            for (int i = 0; i < 4; ++i) {
+              lane = shuffle_helper & 0xff;
+              CHECK_GE(lane, 4);
+              shuffle_helper >>= 8;
+            }
+          }
+        }
         uint32_t i8 = 0;
         for (int i = 0; i < 4; i++) {
-          int lane = shuffle & 0xff;
+          lane = shuffle & 0xff;
+          if (lane >= 4) {
+            lane -= 4;
+          }
           DCHECK_GT(4, lane);
           i8 |= lane << (2 * i);
           shuffle >>= 8;

src/compiler/mips64/code-generator-mips64.cc

@@ -2862,9 +2862,26 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
 
       if (src0 == src1) {
         // Unary S32x4 shuffles are handled with shf.w instruction
+        unsigned lane = shuffle & 0xff;
+        if (FLAG_debug_code) {
+          // range of all four lanes, for unary instruction,
+          // should belong to the same range, which can be one of these:
+          // [0, 3] or [4, 7]
+          if (lane >= 4) {
+            int32_t shuffle_helper = shuffle;
+            for (int i = 0; i < 4; ++i) {
+              lane = shuffle_helper & 0xff;
+              CHECK_GE(lane, 4);
+              shuffle_helper >>= 8;
+            }
+          }
+        }
         uint32_t i8 = 0;
         for (int i = 0; i < 4; i++) {
-          int lane = shuffle & 0xff;
+          lane = shuffle & 0xff;
+          if (lane >= 4) {
+            lane -= 4;
+          }
           DCHECK_GT(4, lane);
           i8 |= lane << (2 * i);
           shuffle >>= 8;