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Diffstat (limited to 'src/3rdparty/v8/src/arm/jump-target-arm.cc')
-rw-r--r-- | src/3rdparty/v8/src/arm/jump-target-arm.cc | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/src/3rdparty/v8/src/arm/jump-target-arm.cc b/src/3rdparty/v8/src/arm/jump-target-arm.cc new file mode 100644 index 0000000..df370c4 --- /dev/null +++ b/src/3rdparty/v8/src/arm/jump-target-arm.cc @@ -0,0 +1,174 @@ +// Copyright 2008 the V8 project authors. All rights reserved. +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following +// disclaimer in the documentation and/or other materials provided +// with the distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived +// from this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include "v8.h" + +#if defined(V8_TARGET_ARCH_ARM) + +#include "codegen-inl.h" +#include "jump-target-inl.h" +#include "register-allocator-inl.h" +#include "virtual-frame-inl.h" + +namespace v8 { +namespace internal { + +// ------------------------------------------------------------------------- +// JumpTarget implementation. + +#define __ ACCESS_MASM(cgen()->masm()) + +void JumpTarget::DoJump() { + ASSERT(cgen()->has_valid_frame()); + // Live non-frame registers are not allowed at unconditional jumps + // because we have no way of invalidating the corresponding results + // which are still live in the C++ code. + ASSERT(cgen()->HasValidEntryRegisters()); + + if (entry_frame_set_) { + if (entry_label_.is_bound()) { + // If we already bound and generated code at the destination then it + // is too late to ask for less optimistic type assumptions. + ASSERT(entry_frame_.IsCompatibleWith(cgen()->frame())); + } + // There already a frame expectation at the target. + cgen()->frame()->MergeTo(&entry_frame_); + cgen()->DeleteFrame(); + } else { + // Clone the current frame to use as the expected one at the target. + set_entry_frame(cgen()->frame()); + // Zap the fall-through frame since the jump was unconditional. + RegisterFile empty; + cgen()->SetFrame(NULL, &empty); + } + if (entry_label_.is_bound()) { + // You can't jump backwards to an already bound label unless you admitted + // up front that this was a bidirectional jump target. Bidirectional jump + // targets will zap their type info when bound in case some later virtual + // frame with less precise type info branches to them. + ASSERT(direction_ != FORWARD_ONLY); + } + __ jmp(&entry_label_); +} + + +void JumpTarget::DoBranch(Condition cond, Hint ignored) { + ASSERT(cgen()->has_valid_frame()); + + if (entry_frame_set_) { + if (entry_label_.is_bound()) { + // If we already bound and generated code at the destination then it + // is too late to ask for less optimistic type assumptions. + ASSERT(entry_frame_.IsCompatibleWith(cgen()->frame())); + } + // We have an expected frame to merge to on the backward edge. + cgen()->frame()->MergeTo(&entry_frame_, cond); + } else { + // Clone the current frame to use as the expected one at the target. + set_entry_frame(cgen()->frame()); + } + if (entry_label_.is_bound()) { + // You can't branch backwards to an already bound label unless you admitted + // up front that this was a bidirectional jump target. Bidirectional jump + // targets will zap their type info when bound in case some later virtual + // frame with less precise type info branches to them. + ASSERT(direction_ != FORWARD_ONLY); + } + __ b(cond, &entry_label_); + if (cond == al) { + cgen()->DeleteFrame(); + } +} + + +void JumpTarget::Call() { + // Call is used to push the address of the catch block on the stack as + // a return address when compiling try/catch and try/finally. We + // fully spill the frame before making the call. The expected frame + // at the label (which should be the only one) is the spilled current + // frame plus an in-memory return address. The "fall-through" frame + // at the return site is the spilled current frame. + ASSERT(cgen()->has_valid_frame()); + // There are no non-frame references across the call. + ASSERT(cgen()->HasValidEntryRegisters()); + ASSERT(!is_linked()); + + // Calls are always 'forward' so we use a copy of the current frame (plus + // one for a return address) as the expected frame. + ASSERT(!entry_frame_set_); + VirtualFrame target_frame = *cgen()->frame(); + target_frame.Adjust(1); + set_entry_frame(&target_frame); + + __ bl(&entry_label_); +} + + +void JumpTarget::DoBind() { + ASSERT(!is_bound()); + + // Live non-frame registers are not allowed at the start of a basic + // block. + ASSERT(!cgen()->has_valid_frame() || cgen()->HasValidEntryRegisters()); + + if (cgen()->has_valid_frame()) { + if (direction_ != FORWARD_ONLY) cgen()->frame()->ForgetTypeInfo(); + // If there is a current frame we can use it on the fall through. + if (!entry_frame_set_) { + entry_frame_ = *cgen()->frame(); + entry_frame_set_ = true; + } else { + cgen()->frame()->MergeTo(&entry_frame_); + // On fall through we may have to merge both ways. + if (direction_ != FORWARD_ONLY) { + // This will not need to adjust the virtual frame entries that are + // register allocated since that was done above and they now match. + // But it does need to adjust the entry_frame_ of this jump target + // to make it potentially less optimistic. Later code can branch back + // to this jump target and we need to assert that that code does not + // have weaker assumptions about types. + entry_frame_.MergeTo(cgen()->frame()); + } + } + } else { + // If there is no current frame we must have an entry frame which we can + // copy. + ASSERT(entry_frame_set_); + RegisterFile empty; + cgen()->SetFrame(new VirtualFrame(&entry_frame_), &empty); + } + + __ bind(&entry_label_); +} + + +#undef __ + + +} } // namespace v8::internal + +#endif // V8_TARGET_ARCH_ARM |