Improve positions recording for calls.

src/arm/assembler-arm.cc

Index: src/arm/assembler-arm.cc
diff --git a/src/arm/assembler-arm.cc b/src/arm/assembler-arm.cc
index ebbd9b1138a5182578d190d1d6ac430fe3940357..d32547ce69a967269b09336592814a945ec07db2 100644
--- a/src/arm/assembler-arm.cc
+++ b/src/arm/assembler-arm.cc
@@ -317,7 +317,8 @@ static const Instr kLdrStrOffsetMask = 0x00000fff;
 static const int kMinimalBufferSize = 4*KB;
 static byte* spare_buffer_ = NULL;
 
-Assembler::Assembler(void* buffer, int buffer_size) {
+Assembler::Assembler(void* buffer, int buffer_size)
+    : positions_recorder_(this) {
   if (buffer == NULL) {
     // Do our own buffer management.
     if (buffer_size <= kMinimalBufferSize) {
@@ -354,10 +355,6 @@ Assembler::Assembler(void* buffer, int buffer_size) {
   no_const_pool_before_ = 0;
   last_const_pool_end_ = 0;
   last_bound_pos_ = 0;
-  current_statement_position_ = RelocInfo::kNoPosition;
-  current_position_ = RelocInfo::kNoPosition;
-  written_statement_position_ = current_statement_position_;
-  written_position_ = current_position_;
 }
 
 
@@ -999,7 +996,7 @@ void Assembler::bl(int branch_offset, Condition cond) {
 
 
 void Assembler::blx(int branch_offset) {  // v5 and above
-  WriteRecordedPositions();
+  positions_recorder()->WriteRecordedPositions();

[Søren Thygesen Gjesse, 2010/11/04 15:08:24]

Why not just positions_recorder_. instead of positions_recorder()->?

   ASSERT((branch_offset & 1) == 0);
   int h = ((branch_offset & 2) >> 1)*B24;
   int imm24 = branch_offset >> 2;
@@ -1009,14 +1006,14 @@ void Assembler::blx(int branch_offset) {  // v5 and above
 
 
 void Assembler::blx(Register target, Condition cond) {  // v5 and above
-  WriteRecordedPositions();
+  positions_recorder()->WriteRecordedPositions();
   ASSERT(!target.is(pc));
   emit(cond | B24 | B21 | 15*B16 | 15*B12 | 15*B8 | 3*B4 | target.code());
 }
 
 
 void Assembler::bx(Register target, Condition cond) {  // v5 and above, plus v4t
-  WriteRecordedPositions();
+  positions_recorder()->WriteRecordedPositions();
   ASSERT(!target.is(pc));  // use of pc is actually allowed, but discouraged
   emit(cond | B24 | B21 | 15*B16 | 15*B12 | 15*B8 | B4 | target.code());
 }
@@ -1114,7 +1111,7 @@ void Assembler::orr(Register dst, Register src1, const Operand& src2,
 
 void Assembler::mov(Register dst, const Operand& src, SBit s, Condition cond) {
   if (dst.is(pc)) {
-    WriteRecordedPositions();
+    positions_recorder()->WriteRecordedPositions();
   }
   // Don't allow nop instructions in the form mov rn, rn to be generated using
   // the mov instruction. They must be generated using nop(int)
@@ -1359,7 +1356,7 @@ void Assembler::msr(SRegisterFieldMask fields, const Operand& src,
 // Load/Store instructions.
 void Assembler::ldr(Register dst, const MemOperand& src, Condition cond) {
   if (dst.is(pc)) {
-    WriteRecordedPositions();
+    positions_recorder()->WriteRecordedPositions();
   }
   addrmod2(cond | B26 | L, dst, src);
 
@@ -2377,14 +2374,14 @@ void Assembler::BlockConstPoolFor(int instructions) {
 
 // Debugging.
 void Assembler::RecordJSReturn() {
-  WriteRecordedPositions();
+  positions_recorder()->WriteRecordedPositions();
   CheckBuffer();
   RecordRelocInfo(RelocInfo::JS_RETURN);
 }
 
 
 void Assembler::RecordDebugBreakSlot() {
-  WriteRecordedPositions();
+  positions_recorder()->WriteRecordedPositions();
   CheckBuffer();
   RecordRelocInfo(RelocInfo::DEBUG_BREAK_SLOT);
 }
@@ -2398,47 +2395,6 @@ void Assembler::RecordComment(const char* msg) {
 }
 
 
-void Assembler::RecordPosition(int pos) {
-  if (pos == RelocInfo::kNoPosition) return;
-  ASSERT(pos >= 0);
-  current_position_ = pos;
-}
-
-
-void Assembler::RecordStatementPosition(int pos) {
-  if (pos == RelocInfo::kNoPosition) return;
-  ASSERT(pos >= 0);
-  current_statement_position_ = pos;
-}
-
-
-bool Assembler::WriteRecordedPositions() {
-  bool written = false;
-
-  // Write the statement position if it is different from what was written last
-  // time.
-  if (current_statement_position_ != written_statement_position_) {
-    CheckBuffer();
-    RecordRelocInfo(RelocInfo::STATEMENT_POSITION, current_statement_position_);
-    written_statement_position_ = current_statement_position_;
-    written = true;
-  }
-
-  // Write the position if it is different from what was written last time and
-  // also different from the written statement position.
-  if (current_position_ != written_position_ &&
-      current_position_ != written_statement_position_) {
-    CheckBuffer();
-    RecordRelocInfo(RelocInfo::POSITION, current_position_);
-    written_position_ = current_position_;
-    written = true;
-  }
-
-  // Return whether something was written.
-  return written;
-}
-
-
 void Assembler::GrowBuffer() {
   if (!own_buffer_) FATAL("external code buffer is too small");