Proper support for deopt_every_n_times option on the x64 and ARM architectures.

R=danno@chromium.org
BUG=

Review URL: https://codereview.chromium.org/62293002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17564 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 8eca27d..c6547be 100644 (file)
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -769,13 +769,39 @@ void LCodeGen::DeoptimizeIf(Condition condition,
     return;
   }
 
-  ASSERT(FLAG_deopt_every_n_times < 2);  // Other values not supported on ARM.
-  if (FLAG_deopt_every_n_times == 1 &&
-      !info()->IsStub() &&
-      info()->opt_count() == id) {
-    ASSERT(frame_is_built_);
-    __ Call(entry, RelocInfo::RUNTIME_ENTRY);
-    return;
+  if (FLAG_deopt_every_n_times != 0 && !info()->IsStub()) {
+    Register scratch = scratch0();
+    ExternalReference count = ExternalReference::stress_deopt_count(isolate());
+
+    // Store the condition on the stack if necessary
+    if (condition != al) {
+      __ mov(scratch, Operand::Zero(), LeaveCC, NegateCondition(condition));
+      __ mov(scratch, Operand(1), LeaveCC, condition);
+      __ push(scratch);
+    }
+
+    __ push(r1);
+    __ mov(scratch, Operand(count));
+    __ ldr(r1, MemOperand(scratch));
+    __ sub(r1, r1, Operand(1), SetCC);
+    __ movw(r1, FLAG_deopt_every_n_times, eq);
+    __ str(r1, MemOperand(scratch));
+    __ pop(r1);
+
+    if (condition != al) {
+      // Clean up the stack before the deoptimizer call
+      __ pop(scratch);
+    }
+
+    __ Call(entry, RelocInfo::RUNTIME_ENTRY, eq);
+
+    // 'Restore' the condition in a slightly hacky way. (It would be better
+    // to use 'msr' and 'mrs' instructions here, but they are not supported by
+    // our ARM simulator).
+    if (condition != al) {
+      condition = ne;
+      __ cmp(scratch, Operand::Zero());
+    }
   }
 
   if (info()->ShouldTrapOnDeopt()) {

diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 14d31c5..a84b569 100644 (file)
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -649,7 +649,27 @@ void LCodeGen::DeoptimizeIf(Condition cc,
     return;
   }
 
-  ASSERT(FLAG_deopt_every_n_times == 0);  // Not yet implemented on x64.
+  if (FLAG_deopt_every_n_times != 0 && !info()->IsStub()) {
+    ExternalReference count = ExternalReference::stress_deopt_count(isolate());
+    Label no_deopt;
+    __ pushfq();
+    __ push(rax);
+    Operand count_operand = masm()->ExternalOperand(count, kScratchRegister);
+    __ movl(rax, count_operand);
+    __ subl(rax, Immediate(1));
+    __ j(not_zero, &no_deopt, Label::kNear);
+    if (FLAG_trap_on_deopt) __ int3();
+    __ movl(rax, Immediate(FLAG_deopt_every_n_times));
+    __ movl(count_operand, rax);
+    __ pop(rax);
+    __ popfq();
+    ASSERT(frame_is_built_);
+    __ call(entry, RelocInfo::RUNTIME_ENTRY);
+    __ bind(&no_deopt);
+    __ movl(count_operand, rax);
+    __ pop(rax);
+    __ popfq();
+  }
 
   if (info()->ShouldTrapOnDeopt()) {
     Label done;