MIPS: [turbofan] Implement Float32Round(TiesEven|RoundUp|RoundDown|Truncate).

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

Index: src/compiler/mips/code-generator-mips.cc
diff --git a/src/compiler/mips/code-generator-mips.cc b/src/compiler/mips/code-generator-mips.cc
index de20ffd84d764169ea4719aad7227347a5f410b2..d03338652ca35536f5364e7f405f8d567eb3cd34 100644
--- a/src/compiler/mips/code-generator-mips.cc
+++ b/src/compiler/mips/code-generator-mips.cc
@@ -192,6 +192,24 @@ class OutOfLineRound : public OutOfLineCode {
 };
 
 
+class OutOfLineRound32 : public OutOfLineCode {
+ public:
+  OutOfLineRound32(CodeGenerator* gen, DoubleRegister result)
+      : OutOfLineCode(gen), result_(result) {}
+
+  void Generate() final {
+    // Handle rounding to zero case where sign has to be preserved.
+    // High bits of float input already in kScratchReg.
+    __ srl(at, kScratchReg, 31);
+    __ sll(at, at, 31);
+    __ mtc1(at, result_);
+  }
+
+ private:
+  DoubleRegister const result_;
+};
+
+
 class OutOfLineTruncate final : public OutOfLineRound {
  public:
   OutOfLineTruncate(CodeGenerator* gen, DoubleRegister result)
@@ -220,6 +238,34 @@ class OutOfLineTiesEven final : public OutOfLineRound {
 };
 
 
+class OutOfLineTruncate32 final : public OutOfLineRound32 {
+ public:
+  OutOfLineTruncate32(CodeGenerator* gen, DoubleRegister result)
+      : OutOfLineRound32(gen, result) {}
+};
+
+
+class OutOfLineFloor32 final : public OutOfLineRound32 {
+ public:
+  OutOfLineFloor32(CodeGenerator* gen, DoubleRegister result)
+      : OutOfLineRound32(gen, result) {}
+};
+
+
+class OutOfLineCeil32 final : public OutOfLineRound32 {
+ public:
+  OutOfLineCeil32(CodeGenerator* gen, DoubleRegister result)
+      : OutOfLineRound32(gen, result) {}
+};
+
+
+class OutOfLineTiesEven32 final : public OutOfLineRound32 {
+ public:
+  OutOfLineTiesEven32(CodeGenerator* gen, DoubleRegister result)
+      : OutOfLineRound32(gen, result) {}
+};
+
+
 class OutOfLineRecordWrite final : public OutOfLineCode {
  public:
   OutOfLineRecordWrite(CodeGenerator* gen, Register object, Register index,
@@ -453,6 +499,27 @@ FPUCondition FlagsConditionToConditionCmpFPU(bool& predicate,
   } while (0)
 
 
+#define ASSEMBLE_ROUND_FLOAT_TO_FLOAT(asm_instr, operation)                    \
+  do {                                                                         \
+    int32_t kFloat32ExponentBias = 127;                                        \
+    int32_t kFloat32MantissaBits = 23;                                         \
+    int32_t kFloat32ExponentBits = 8;                                          \
+    auto ool =                                                                 \
+        new (zone()) OutOfLine##operation##32(this, i.OutputDoubleRegister()); \
+    Label done;                                                                \
+    __ mtc1(kScratchReg, i.InputDoubleRegister(0));                            \
+    __ Ext(at, kScratchReg, kFloat32MantissaBits, kFloat32ExponentBits);       \
+    __ Branch(USE_DELAY_SLOT, &done, hs, at,                                   \
+              Operand(kFloat32ExponentBias + kFloat32MantissaBits));           \
+    __ mov_s(i.OutputDoubleRegister(), i.InputDoubleRegister(0));              \
+    __ asm_instr(i.OutputDoubleRegister(), i.InputDoubleRegister(0));          \
+    __ mfc1(at, i.OutputDoubleRegister());                                     \
+    __ Branch(USE_DELAY_SLOT, ool->entry(), eq, at, Operand(zero_reg));        \
+    __ cvt_s_w(i.OutputDoubleRegister(), i.OutputDoubleRegister());            \
+    __ bind(ool->exit());                                                      \
+    __ bind(&done);                                                            \
+  } while (0)
+
 void CodeGenerator::AssembleDeconstructActivationRecord(int stack_param_delta) {
   int sp_slot_delta = TailCallFrameStackSlotDelta(stack_param_delta);
   if (sp_slot_delta > 0) {
@@ -813,18 +880,34 @@ void CodeGenerator::AssembleArchInstruction(Instruction* instr) {
       ASSEMBLE_ROUND_DOUBLE_TO_DOUBLE(floor_l_d, Floor);
       break;
     }
+    case kMipsFloat32RoundDown: {
+      ASSEMBLE_ROUND_FLOAT_TO_FLOAT(floor_w_s, Floor);
+      break;
+    }
     case kMipsFloat64RoundTruncate: {
       ASSEMBLE_ROUND_DOUBLE_TO_DOUBLE(trunc_l_d, Truncate);
       break;
     }
+    case kMipsFloat32RoundTruncate: {
+      ASSEMBLE_ROUND_FLOAT_TO_FLOAT(trunc_w_s, Truncate);
+      break;
+    }
     case kMipsFloat64RoundUp: {
       ASSEMBLE_ROUND_DOUBLE_TO_DOUBLE(ceil_l_d, Ceil);
       break;
     }
+    case kMipsFloat32RoundUp: {
+      ASSEMBLE_ROUND_FLOAT_TO_FLOAT(ceil_w_s, Ceil);
+      break;
+    }
     case kMipsFloat64RoundTiesEven: {
       ASSEMBLE_ROUND_DOUBLE_TO_DOUBLE(round_l_d, TiesEven);
       break;
     }
+    case kMipsFloat32RoundTiesEven: {
+      ASSEMBLE_ROUND_FLOAT_TO_FLOAT(round_w_s, TiesEven);
+      break;
+    }
     case kMipsFloat64Max: {
       // (b < a) ? a : b
       if (IsMipsArchVariant(kMips32r6)) {