x64: Add MulI and DivI to lithium instructions.

src/x64/lithium-codegen-x64.cc

Index: src/x64/lithium-codegen-x64.cc
===================================================================
--- src/x64/lithium-codegen-x64.cc	(revision 6669)
+++ src/x64/lithium-codegen-x64.cc	(working copy)
@@ -608,13 +608,94 @@
 
 
 void LCodeGen::DoDivI(LDivI* instr) {
-  Abort("Unimplemented: %s", "DoDivI");}
+  LOperand* right = instr->InputAt(1);
+  ASSERT(ToRegister(instr->result()).is(rax));
+  ASSERT(ToRegister(instr->InputAt(0)).is(rax));
+  ASSERT(!ToRegister(instr->InputAt(1)).is(rax));
+  ASSERT(!ToRegister(instr->InputAt(1)).is(rdx));
 
+  Register left_reg = rax;
 
+  // Check for x / 0.
+  Register right_reg = ToRegister(right);
+  if (instr->hydrogen()->CheckFlag(HValue::kCanBeDivByZero)) {
+    __ testl(right_reg, right_reg);
+    DeoptimizeIf(zero, instr->environment());
+  }
+
+  // Check for (0 / -x) that will produce negative zero.
+  if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
+    NearLabel left_not_zero;

[William Hesse, 2011/02/08 09:42:47]

Should we combine the zero test and the Min-int test into
test(left_reg, Immediate(0x7FFFFFFF)
j(not_zero, &safe);
...
further tests

[Rico, 2011/02/08 11:22:04]

I guess combining these could cause us to deoptimize in cases where we would not
need to deoptimize normally? (e.g., if we should not bailout on minus zero, but
we can overflow)

+    __ testl(left_reg, left_reg);
+    __ j(not_zero, &left_not_zero);
+    __ testl(right_reg, right_reg);
+    DeoptimizeIf(sign, instr->environment());
+    __ bind(&left_not_zero);
+  }
+
+  // Check for (-kMinInt / -1).
+  if (instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
+    NearLabel left_not_min_int;
+    __ cmpl(left_reg, Immediate(kMinInt));
+    __ j(not_zero, &left_not_min_int);
+    __ cmpl(right_reg, Immediate(-1));
+    DeoptimizeIf(zero, instr->environment());
+    __ bind(&left_not_min_int);
+  }
+
+  // Sign extend to rdx.
+  __ cdq();
+  __ idivl(right_reg);
+
+  // Deoptimize if remainder is not 0.
+  __ testl(rdx, rdx);
+  DeoptimizeIf(not_zero, instr->environment());
+}
+
+
 void LCodeGen::DoMulI(LMulI* instr) {
-  Abort("Unimplemented: %s", "DoMultI");}
+  Register left = ToRegister(instr->InputAt(0));
+  LOperand* right = instr->InputAt(1);
 
+  if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
+    __ movl(kScratchRegister, left);
+  }
 
+  if (right->IsConstantOperand()) {
+    int right_value = ToInteger32(LConstantOperand::cast(right));
+    __ imull(left, left, Immediate(right_value));
+  } else if (right->IsStackSlot()) {
+    __ imul(left, ToOperand(right));
+  } else {
+    __ imull(left, ToRegister(right));
+  }
+
+  if (instr->hydrogen()->CheckFlag(HValue::kCanOverflow)) {
+    DeoptimizeIf(overflow, instr->environment());
+  }
+
+  if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
+    // Bail out if the result is supposed to be negative zero.
+    NearLabel done;
+    __ testl(left, left);
+    __ j(not_zero, &done);
+    if (right->IsConstantOperand()) {
+      if (ToInteger32(LConstantOperand::cast(right)) < 0) {

[William Hesse, 2011/02/08 09:42:47]

What about the case where right is constant 0?  And left is negative.

[Rico, 2011/02/08 11:22:04]

Fixed - here and on ia32 and arm. Bug and regression test added

+        DeoptimizeIf(no_condition, instr->environment());
+      }
+    } else if (right->IsStackSlot()) {
+      __ or_(kScratchRegister, ToOperand(right));
+      DeoptimizeIf(sign, instr->environment());
+    } else {
+      // Test the non-zero operand for negative sign.
+      __ or_(kScratchRegister, ToRegister(right));
+      DeoptimizeIf(sign, instr->environment());
+    }
+    __ bind(&done);
+  }
+}
+
+
 void LCodeGen::DoBitI(LBitI* instr) {
   LOperand* left = instr->InputAt(0);
   LOperand* right = instr->InputAt(1);