Revision: 20023
Author: [email protected]
Date: Tue Mar 18 11:36:19 2014 UTC
Log: Add support for movw/movt immediate loads to BackEdgeTable on ARM
to enable ool constant pool.
[email protected], [email protected]
Review URL: https://codereview.chromium.org/190833002
http://code.google.com/p/v8/source/detail?r=20023
Modified:
/branches/bleeding_edge/src/arm/full-codegen-arm.cc
=======================================
--- /branches/bleeding_edge/src/arm/full-codegen-arm.cc Mon Mar 17 17:29:03
2014 UTC
+++ /branches/bleeding_edge/src/arm/full-codegen-arm.cc Tue Mar 18 11:36:19
2014 UTC
@@ -4827,7 +4827,19 @@
#undef __
-static const int32_t kBranchBeforeInterrupt = 0x5a000004;
+static Address GetInterruptImmediateLoadAddress(Address pc) {
+ Address load_address = pc - 2 * Assembler::kInstrSize;
+ if (!FLAG_enable_ool_constant_pool) {
+
ASSERT(Assembler::IsLdrPcImmediateOffset(Memory::int32_at(load_address)));
+ } else if (Assembler::IsMovT(Memory::int32_at(load_address))) {
+ load_address -= Assembler::kInstrSize;
+ ASSERT(Assembler::IsMovW(Memory::int32_at(load_address)));
+ } else {
+ // TODO(rmcilroy): uncomment when IsLdrPpImmediateOffset lands.
+ // ASSERT(IsLdrPpImmediateOffset(Memory::int32_at(load_address)));
+ }
+ return load_address;
+}
void BackEdgeTable::PatchAt(Code* unoptimized_code,
@@ -4835,37 +4847,42 @@
BackEdgeState target_state,
Code* replacement_code) {
static const int kInstrSize = Assembler::kInstrSize;
- Address branch_address = pc - 3 * kInstrSize;
+ Address pc_immediate_load_address = GetInterruptImmediateLoadAddress(pc);
+ Address branch_address = pc_immediate_load_address - kInstrSize;
CodePatcher patcher(branch_address, 1);
-
switch (target_state) {
case INTERRUPT:
+ {
// <decrement profiling counter>
- // 2a 00 00 01 bpl ok
- // e5 9f c? ?? ldr ip, [pc, <interrupt stub address>]
- // e1 2f ff 3c blx ip
+ // bpl ok
+ // ; load interrupt stub address into ip - either of:
+ // ldr ip, [pc/pp, <constant pool offset>] | movw ip, <immed
low>
+ // | movt ip, <immed
high>
+ // blx ip
// ok-label
- patcher.masm()->b(4 * kInstrSize, pl); // Jump offset is 4
instructions.
- ASSERT_EQ(kBranchBeforeInterrupt, Memory::int32_at(branch_address));
+
+ // Calculate branch offet to the ok-label - this is the difference
between
+ // the branch address and |pc| (which points at <blx ip>) plus one
instr.
+ int branch_offset = pc + kInstrSize - branch_address;
+ patcher.masm()->b(branch_offset, pl);
break;
+ }
case ON_STACK_REPLACEMENT:
case OSR_AFTER_STACK_CHECK:
// <decrement profiling counter>
- // e1 a0 00 00 mov r0, r0 (NOP)
- // e5 9f c? ?? ldr ip, [pc, <on-stack replacement address>]
- // e1 2f ff 3c blx ip
+ // mov r0, r0 (NOP)
+ // ; load on-stack replacement address into ip - either of:
+ // ldr ip, [pc/pp, <constant pool offset>] | movw ip, <immed
low>
+ // | movt ip, <immed
high>
+ // blx ip
// ok-label
patcher.masm()->nop();
break;
}
- Address pc_immediate_load_address = pc - 2 * kInstrSize;
// Replace the call address.
- uint32_t interrupt_address_offset =
- Memory::uint16_at(pc_immediate_load_address) & 0xfff;
- Address interrupt_address_pointer = pc + interrupt_address_offset;
- Memory::uint32_at(interrupt_address_pointer) =
- reinterpret_cast<uint32_t>(replacement_code->entry());
+ Assembler::set_target_address_at(pc_immediate_load_address,
unoptimized_code,
+ replacement_code->entry());
unoptimized_code->GetHeap()->incremental_marking()->RecordCodeTargetPatch(
unoptimized_code, pc_immediate_load_address, replacement_code);
@@ -4879,34 +4896,26 @@
static const int kInstrSize = Assembler::kInstrSize;
ASSERT(Memory::int32_at(pc - kInstrSize) == kBlxIp);
- Address branch_address = pc - 3 * kInstrSize;
- Address pc_immediate_load_address = pc - 2 * kInstrSize;
- uint32_t interrupt_address_offset =
- Memory::uint16_at(pc_immediate_load_address) & 0xfff;
- Address interrupt_address_pointer = pc + interrupt_address_offset;
+ Address pc_immediate_load_address = GetInterruptImmediateLoadAddress(pc);
+ Address branch_address = pc_immediate_load_address - kInstrSize;
+ Address interrupt_address = Assembler::target_address_at(
+ pc_immediate_load_address, unoptimized_code);
- if (Memory::int32_at(branch_address) == kBranchBeforeInterrupt) {
- ASSERT(Memory::uint32_at(interrupt_address_pointer) ==
- reinterpret_cast<uint32_t>(
- isolate->builtins()->InterruptCheck()->entry()));
- ASSERT(Assembler::IsLdrPcImmediateOffset(
- Assembler::instr_at(pc_immediate_load_address)));
+ if (Assembler::IsBranch(Assembler::instr_at(branch_address))) {
+ ASSERT(interrupt_address ==
+ isolate->builtins()->InterruptCheck()->entry());
return INTERRUPT;
}
ASSERT(Assembler::IsNop(Assembler::instr_at(branch_address)));
- ASSERT(Assembler::IsLdrPcImmediateOffset(
- Assembler::instr_at(pc_immediate_load_address)));
- if (Memory::uint32_at(interrupt_address_pointer) ==
- reinterpret_cast<uint32_t>(
- isolate->builtins()->OnStackReplacement()->entry())) {
+ if (interrupt_address ==
+ isolate->builtins()->OnStackReplacement()->entry()) {
return ON_STACK_REPLACEMENT;
}
- ASSERT(Memory::uint32_at(interrupt_address_pointer) ==
- reinterpret_cast<uint32_t>(
- isolate->builtins()->OsrAfterStackCheck()->entry()));
+ ASSERT(interrupt_address ==
+ isolate->builtins()->OsrAfterStackCheck()->entry());
return OSR_AFTER_STACK_CHECK;
}
--
--
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