MIPS[64]: Fix jump_tables6 test for r6 architectures

This patch fixes jump_tables6 test for mips32r6 and mips64r6.
This is regression from CL:
https://crrev.com/d735f3ab12061f0a588b3f0538f9229cf747f818

BUG=

Review-Url: https://codereview.chromium.org/2547033002
Cr-Commit-Position: refs/heads/master@{#41543}

src/mips/assembler-mips.h

@@ -552,6 +552,17 @@ class Assembler : public AssemblerBase {
   static const int kDebugBreakSlotLength =
       kDebugBreakSlotInstructions * kInstrSize;
 
+  // Max offset for instructions with 16-bit offset field
+  static const int kMaxBranchOffset = (1 << (18 - 1)) - 1;
+
+  // Max offset for compact branch instructions with 26-bit offset field
+  static const int kMaxCompactBranchOffset = (1 << (28 - 1)) - 1;
+
+#ifdef _MIPS_ARCH_MIPS32R6
+  static const int kTrampolineSlotsSize = 2 * kInstrSize;
+#else
+  static const int kTrampolineSlotsSize = 4 * kInstrSize;
+#endif
 
   // ---------------------------------------------------------------------------
   // Code generation.
@@ -1166,6 +1177,9 @@ class Assembler : public AssemblerBase {
   }
 
   bool IsPrevInstrCompactBranch() { return prev_instr_compact_branch_; }
+  static bool IsCompactBranchSupported() {
+    return IsMipsArchVariant(kMips32r6);
+  }
 
   inline int UnboundLabelsCount() { return unbound_labels_count_; }
 
@@ -1440,13 +1454,6 @@ class Assembler : public AssemblerBase {
   // branch instruction generation, where we use jump instructions rather
   // than regular branch instructions.
   bool trampoline_emitted_;
-#ifdef _MIPS_ARCH_MIPS32R6
-  static const int kTrampolineSlotsSize = 2 * kInstrSize;
-#else
-  static const int kTrampolineSlotsSize = 4 * kInstrSize;
-#endif
-  static const int kMaxBranchOffset = (1 << (18 - 1)) - 1;
-  static const int kMaxCompactBranchOffset = (1 << (28 - 1)) - 1;
   static const int kInvalidSlotPos = -1;
 
   // Internal reference positions, required for unbounded internal reference

src/mips/macro-assembler-mips.h

@@ -208,6 +208,12 @@ class MacroAssembler: public Assembler {
               Heap::RootListIndex index,
               BranchDelaySlot bdslot = PROTECT);
 
+// Number of instructions needed for calculation of switch table entry address
+#ifdef _MIPS_ARCH_MIPS32R6
+  static const int kSwitchTablePrologueSize = 5;
+#else
+  static const int kSwitchTablePrologueSize = 10;
+#endif
   // GetLabelFunction must be lambda '[](size_t index) -> Label*' or a
   // functor/function with 'Label *func(size_t index)' declaration.
   template <typename Func>
@@ -1832,13 +1838,13 @@ template <typename Func>
 void MacroAssembler::GenerateSwitchTable(Register index, size_t case_count,
                                          Func GetLabelFunction) {
   if (kArchVariant >= kMips32r6) {
-    BlockTrampolinePoolFor(case_count + 5);
+    BlockTrampolinePoolFor(case_count + kSwitchTablePrologueSize);
     addiupc(at, 5);
     Lsa(at, at, index, kPointerSizeLog2);
     lw(at, MemOperand(at));
   } else {
     Label here;
-    BlockTrampolinePoolFor(case_count + 10);
+    BlockTrampolinePoolFor(case_count + kSwitchTablePrologueSize);
     push(ra);
     bal(&here);
     sll(at, index, kPointerSizeLog2);  // Branch delay slot.

src/mips64/assembler-mips64.h

@@ -559,6 +559,13 @@ class Assembler : public AssemblerBase {
   static const int kDebugBreakSlotLength =
       kDebugBreakSlotInstructions * kInstrSize;
 
+  // Max offset for instructions with 16-bit offset field
+  static const int kMaxBranchOffset = (1 << (18 - 1)) - 1;
+
+  // Max offset for compact branch instructions with 26-bit offset field
+  static const int kMaxCompactBranchOffset = (1 << (28 - 1)) - 1;
+
+  static const int kTrampolineSlotsSize = 2 * kInstrSize;
 
   // ---------------------------------------------------------------------------
   // Code generation.
@@ -1223,6 +1230,7 @@ class Assembler : public AssemblerBase {
   }
 
   bool IsPrevInstrCompactBranch() { return prev_instr_compact_branch_; }
+  static bool IsCompactBranchSupported() { return kArchVariant == kMips64r6; }
 
   inline int UnboundLabelsCount() { return unbound_labels_count_; }
 
@@ -1495,9 +1503,6 @@ class Assembler : public AssemblerBase {
   // branch instruction generation, where we use jump instructions rather
   // than regular branch instructions.
   bool trampoline_emitted_;
-  static const int kTrampolineSlotsSize = 2 * kInstrSize;
-  static const int kMaxBranchOffset = (1 << (18 - 1)) - 1;
-  static const int kMaxCompactBranchOffset = (1 << (28 - 1)) - 1;
   static const int kInvalidSlotPos = -1;
 
   // Internal reference positions, required for unbounded internal reference

src/mips64/macro-assembler-mips64.h

@@ -236,6 +236,13 @@ class MacroAssembler: public Assembler {
               Heap::RootListIndex index,
               BranchDelaySlot bdslot = PROTECT);
 
+// Number of instructions needed for calculation of switch table entry address
+#ifdef _MIPS_ARCH_MIPS64R6
+  static const int kSwitchTablePrologueSize = 6;
+#else
+  static const int kSwitchTablePrologueSize = 11;
+#endif
+
   // GetLabelFunction must be lambda '[](size_t index) -> Label*' or a
   // functor/function with 'Label *func(size_t index)' declaration.
   template <typename Func>
@@ -1974,7 +1981,8 @@ void MacroAssembler::GenerateSwitchTable(Register index, size_t case_count,
   // Ensure that dd-ed labels following this instruction use 8 bytes aligned
   // addresses.
   if (kArchVariant >= kMips64r6) {
-    BlockTrampolinePoolFor(static_cast<int>(case_count) * 2 + 6);
+    BlockTrampolinePoolFor(static_cast<int>(case_count) * 2 +
+                           kSwitchTablePrologueSize);
     // Opposite of Align(8) as we have odd number of instructions in this case.
     if ((pc_offset() & 7) == 0) {
       nop();
@@ -1984,7 +1992,8 @@ void MacroAssembler::GenerateSwitchTable(Register index, size_t case_count,
     ld(at, MemOperand(at));
   } else {
     Label here;
-    BlockTrampolinePoolFor(static_cast<int>(case_count) * 2 + 11);
+    BlockTrampolinePoolFor(static_cast<int>(case_count) * 2 +
+                           kSwitchTablePrologueSize);
     Align(8);
     push(ra);
     bal(&here);

test/cctest/test-macro-assembler-mips.cc

@@ -297,16 +297,21 @@ TEST(jump_tables6) {
                            v8::internal::CodeObjectRequired::kYes);
   MacroAssembler* masm = &assembler;
 
-  const int kNumCases = 40;
+  const int kSwitchTableCases = 40;
-  const int kFillInstr = 32551;
+
-  const int kMaxBranchOffset = (1 << (18 - 1)) - 1;
+  const int kInstrSize = Assembler::kInstrSize;
-  const int kTrampolineSlotsSize = 4 * Instruction::kInstrSize;
+  const int kMaxBranchOffset = Assembler::kMaxBranchOffset;
+  const int kTrampolineSlotsSize = Assembler::kTrampolineSlotsSize;
+  const int kSwitchTablePrologueSize = MacroAssembler::kSwitchTablePrologueSize;
+
   const int kMaxOffsetForTrampolineStart =
       kMaxBranchOffset - 16 * kTrampolineSlotsSize;
+  const int kFillInstr = (kMaxOffsetForTrampolineStart / kInstrSize) -
+                         (kSwitchTablePrologueSize + kSwitchTableCases) - 20;
 
-  int values[kNumCases];
+  int values[kSwitchTableCases];
   isolate->random_number_generator()->NextBytes(values, sizeof(values));
-  Label labels[kNumCases];
+  Label labels[kSwitchTableCases];
   Label near_start, end, done;
 
   __ Push(ra);
@@ -316,7 +321,7 @@ TEST(jump_tables6) {
   int gen_insn = 0;
 
   __ Branch(&end);
-  gen_insn += 2;
+  gen_insn += Assembler::IsCompactBranchSupported() ? 1 : 2;
   __ bind(&near_start);
 
   // Generate slightly less than 32K instructions, which will soon require
@@ -326,23 +331,24 @@ TEST(jump_tables6) {
   }
   gen_insn += kFillInstr;
 
-  __ GenerateSwitchTable(a0, kNumCases,
+  __ GenerateSwitchTable(a0, kSwitchTableCases,
                          [&labels](size_t i) { return labels + i; });
-  gen_insn += (10 + kNumCases);
+  gen_insn += (kSwitchTablePrologueSize + kSwitchTableCases);
 
-  for (int i = 0; i < kNumCases; ++i) {
+  for (int i = 0; i < kSwitchTableCases; ++i) {
     __ bind(&labels[i]);
     __ li(v0, values[i]);
     __ Branch(&done);
   }
-  gen_insn += (4 * kNumCases);
+  gen_insn +=
+      ((Assembler::IsCompactBranchSupported() ? 3 : 4) * kSwitchTableCases);
 
   // If offset from here to first branch instr is greater than max allowed
   // offset for trampoline ...
   CHECK_LT(kMaxOffsetForTrampolineStart, masm->pc_offset() - offs1);
   // ... number of generated instructions must be greater then "gen_insn",
   // as we are expecting trampoline generation
-  CHECK_LT(gen_insn, (masm->pc_offset() - offs1) / Instruction::kInstrSize);
+  CHECK_LT(gen_insn, (masm->pc_offset() - offs1) / kInstrSize);
 
   __ bind(&done);
   __ Pop(ra);
@@ -360,7 +366,7 @@ TEST(jump_tables6) {
   code->Print(std::cout);
 #endif
   F1 f = FUNCTION_CAST<F1>(code->entry());
-  for (int i = 0; i < kNumCases; ++i) {
+  for (int i = 0; i < kSwitchTableCases; ++i) {
     int res =
         reinterpret_cast<int>(CALL_GENERATED_CODE(isolate, f, i, 0, 0, 0, 0));
     ::printf("f(%d) = %d\n", i, res);

test/cctest/test-macro-assembler-mips64.cc

@@ -365,16 +365,22 @@ TEST(jump_tables6) {
                            v8::internal::CodeObjectRequired::kYes);
   MacroAssembler* masm = &assembler;
 
-  const int kNumCases = 40;
+  const int kSwitchTableCases = 40;
-  const int kFillInstr = 32551;
+
-  const int kMaxBranchOffset = (1 << (18 - 1)) - 1;
+  const int kInstrSize = Assembler::kInstrSize;
-  const int kTrampolineSlotsSize = 2 * Instruction::kInstrSize;
+  const int kMaxBranchOffset = Assembler::kMaxBranchOffset;
+  const int kTrampolineSlotsSize = Assembler::kTrampolineSlotsSize;
+  const int kSwitchTablePrologueSize = MacroAssembler::kSwitchTablePrologueSize;
+
   const int kMaxOffsetForTrampolineStart =
       kMaxBranchOffset - 16 * kTrampolineSlotsSize;
+  const int kFillInstr = (kMaxOffsetForTrampolineStart / kInstrSize) -
+                         (kSwitchTablePrologueSize + 2 * kSwitchTableCases) -
+                         20;
 
-  int values[kNumCases];
+  int values[kSwitchTableCases];
   isolate->random_number_generator()->NextBytes(values, sizeof(values));
-  Label labels[kNumCases];
+  Label labels[kSwitchTableCases];
   Label near_start, end, done;
 
   __ Push(ra);
@@ -384,7 +390,7 @@ TEST(jump_tables6) {
   int gen_insn = 0;
 
   __ Branch(&end);
-  gen_insn += 2;
+  gen_insn += Assembler::IsCompactBranchSupported() ? 1 : 2;
   __ bind(&near_start);
 
   // Generate slightly less than 32K instructions, which will soon require
@@ -394,23 +400,24 @@ TEST(jump_tables6) {
   }
   gen_insn += kFillInstr;
 
-  __ GenerateSwitchTable(a0, kNumCases,
+  __ GenerateSwitchTable(a0, kSwitchTableCases,
                          [&labels](size_t i) { return labels + i; });
-  gen_insn += (11 + 2 * kNumCases);
+  gen_insn += (kSwitchTablePrologueSize + 2 * kSwitchTableCases);
 
-  for (int i = 0; i < kNumCases; ++i) {
+  for (int i = 0; i < kSwitchTableCases; ++i) {
     __ bind(&labels[i]);
     __ li(v0, values[i]);
     __ Branch(&done);
   }
-  gen_insn += (4 * kNumCases);
+  gen_insn +=
+      ((Assembler::IsCompactBranchSupported() ? 3 : 4) * kSwitchTableCases);
 
   // If offset from here to first branch instr is greater than max allowed
   // offset for trampoline ...
   CHECK_LT(kMaxOffsetForTrampolineStart, masm->pc_offset() - offs1);
   // ... number of generated instructions must be greater then "gen_insn",
   // as we are expecting trampoline generation
-  CHECK_LT(gen_insn, (masm->pc_offset() - offs1) / Instruction::kInstrSize);
+  CHECK_LT(gen_insn, (masm->pc_offset() - offs1) / kInstrSize);
 
   __ bind(&done);
   __ Pop(ra);
@@ -428,7 +435,7 @@ TEST(jump_tables6) {
   code->Print(std::cout);
 #endif
   F1 f = FUNCTION_CAST<F1>(code->entry());
-  for (int i = 0; i < kNumCases; ++i) {
+  for (int i = 0; i < kSwitchTableCases; ++i) {
     int64_t res = reinterpret_cast<int64_t>(
         CALL_GENERATED_CODE(isolate, f, i, 0, 0, 0, 0));
     ::printf("f(%d) = %" PRId64 "\n", i, res);