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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /js/src/jit/x86-shared/Patching-x86-shared.h
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
Diffstat (limited to 'js/src/jit/x86-shared/Patching-x86-shared.h')
-rw-r--r--js/src/jit/x86-shared/Patching-x86-shared.h124
1 files changed, 124 insertions, 0 deletions
diff --git a/js/src/jit/x86-shared/Patching-x86-shared.h b/js/src/jit/x86-shared/Patching-x86-shared.h
new file mode 100644
index 000000000..b73492870
--- /dev/null
+++ b/js/src/jit/x86-shared/Patching-x86-shared.h
@@ -0,0 +1,124 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef jit_x86_shared_Patching_x86_shared_h
+#define jit_x86_shared_Patching_x86_shared_h
+
+namespace js {
+namespace jit {
+
+namespace X86Encoding {
+
+inline void*
+GetPointer(const void* where)
+{
+ void* res;
+ memcpy(&res, (const char*)where - sizeof(void*), sizeof(void*));
+ return res;
+}
+
+inline void
+SetPointer(void* where, const void* value)
+{
+ memcpy((char*)where - sizeof(void*), &value, sizeof(void*));
+}
+
+inline int32_t
+GetInt32(const void* where)
+{
+ int32_t res;
+ memcpy(&res, (const char*)where - sizeof(int32_t), sizeof(int32_t));
+ return res;
+}
+
+inline void
+SetInt32(void* where, int32_t value)
+{
+ memcpy((char*)where - sizeof(int32_t), &value, sizeof(int32_t));
+}
+
+inline void
+SetRel32(void* from, void* to)
+{
+ intptr_t offset = reinterpret_cast<intptr_t>(to) - reinterpret_cast<intptr_t>(from);
+ MOZ_ASSERT(offset == static_cast<int32_t>(offset),
+ "offset is too great for a 32-bit relocation");
+ if (offset != static_cast<int32_t>(offset))
+ MOZ_CRASH("offset is too great for a 32-bit relocation");
+
+ SetInt32(from, offset);
+}
+
+inline void*
+GetRel32Target(void* where)
+{
+ int32_t rel = GetInt32(where);
+ return (char*)where + rel;
+}
+
+class JmpSrc {
+ public:
+ JmpSrc()
+ : offset_(-1)
+ {
+ }
+
+ explicit JmpSrc(int32_t offset)
+ : offset_(offset)
+ {
+ }
+
+ int32_t offset() const {
+ return offset_;
+ }
+
+ bool isSet() const {
+ return offset_ != -1;
+ }
+
+ private:
+ int offset_;
+};
+
+class JmpDst {
+ public:
+ JmpDst()
+ : offset_(-1)
+ , used_(false)
+ {
+ }
+
+ bool isUsed() const { return used_; }
+ void used() { used_ = true; }
+ bool isValid() const { return offset_ != -1; }
+
+ explicit JmpDst(int32_t offset)
+ : offset_(offset)
+ , used_(false)
+ {
+ MOZ_ASSERT(offset_ == offset);
+ }
+ int32_t offset() const {
+ return offset_;
+ }
+ private:
+ int32_t offset_ : 31;
+ bool used_ : 1;
+};
+
+inline bool
+CanRelinkJump(void* from, void* to)
+{
+ intptr_t offset = static_cast<char*>(to) - static_cast<char*>(from);
+ return (offset == static_cast<int32_t>(offset));
+}
+
+} // namespace X86Encoding
+
+} // namespace jit
+} // namespace js
+
+#endif /* jit_x86_shared_Patching_x86_shared_h */