diff options
Diffstat (limited to 'source/l/mozjs60/patches/Save-x28-before-clobbering-it-in-the-regex-compiler.patch')
| -rw-r--r-- | source/l/mozjs60/patches/Save-x28-before-clobbering-it-in-the-regex-compiler.patch | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/source/l/mozjs60/patches/Save-x28-before-clobbering-it-in-the-regex-compiler.patch b/source/l/mozjs60/patches/Save-x28-before-clobbering-it-in-the-regex-compiler.patch new file mode 100644 index 000000000..3886c0e9b --- /dev/null +++ b/source/l/mozjs60/patches/Save-x28-before-clobbering-it-in-the-regex-compiler.patch @@ -0,0 +1,97 @@ +# HG changeset patch +# User Lars T Hansen <lhansen@mozilla.com> +# Date 1521449886 -3600 +# Node ID 903a79a1efff18fc7cc50db09a3fe5d768adc9a8 +# Parent 4d2955a9ca7e30ca4c3af9c214ccc77fb2fe7fb8 +Bug 1445907 - Save x28 before clobbering it in the regex compiler. r=sstangl + +Origin: upstream +Applied-upstream: 61, commit: https://hg.mozilla.org/mozilla-central/rev/903a79a1efff +--- +diff --git a/js/src/irregexp/NativeRegExpMacroAssembler.cpp b/js/src/irregexp/NativeRegExpMacroAssembler.cpp +--- a/js/src/irregexp/NativeRegExpMacroAssembler.cpp ++++ b/js/src/irregexp/NativeRegExpMacroAssembler.cpp +@@ -118,17 +118,25 @@ NativeRegExpMacroAssembler::GenerateCode + + Label return_temp0; + + // Finalize code - write the entry point code now we know how many + // registers we need. + masm.bind(&entry_label_); + + #ifdef JS_CODEGEN_ARM64 +- // ARM64 communicates stack address via sp, but uses a pseudo-sp for addressing. ++ // ARM64 communicates stack address via SP, but uses a pseudo-sp (PSP) for ++ // addressing. The register we use for PSP may however also be used by ++ // calling code, and it is nonvolatile, so save it. Do this as a special ++ // case first because the generic save/restore code needs the PSP to be ++ // initialized already. ++ MOZ_ASSERT(PseudoStackPointer64.Is(masm.GetStackPointer64())); ++ masm.Str(PseudoStackPointer64, vixl::MemOperand(sp, -16, vixl::PreIndex)); ++ ++ // Initialize the PSP from the SP. + masm.initStackPtr(); + #endif + + // Push non-volatile registers which might be modified by jitcode. + size_t pushedNonVolatileRegisters = 0; + for (GeneralRegisterForwardIterator iter(savedNonVolatileRegisters); iter.more(); ++iter) { + masm.Push(*iter); + pushedNonVolatileRegisters++; +@@ -416,17 +424,32 @@ NativeRegExpMacroAssembler::GenerateCode + masm.pop(temp0); + masm.movePtr(temp0, StackPointer); + #endif + + // Restore non-volatile registers which were saved on entry. + for (GeneralRegisterBackwardIterator iter(savedNonVolatileRegisters); iter.more(); ++iter) + masm.Pop(*iter); + ++#ifdef JS_CODEGEN_ARM64 ++ // Now restore the value that was in the PSP register on entry, and return. ++ ++ // Obtain the correct SP from the PSP. ++ masm.Mov(sp, PseudoStackPointer64); ++ ++ // Restore the saved value of the PSP register, this value is whatever the ++ // caller had saved in it, not any actual SP value, and it must not be ++ // overwritten subsequently. ++ masm.Ldr(PseudoStackPointer64, vixl::MemOperand(sp, 16, vixl::PostIndex)); ++ ++ // Perform a plain Ret(), as abiret() will move SP <- PSP and that is wrong. ++ masm.Ret(vixl::lr); ++#else + masm.abiret(); ++#endif + + // Backtrack code (branch target for conditional backtracks). + if (backtrack_label_.used()) { + masm.bind(&backtrack_label_); + Backtrack(); + } + + // Backtrack stack overflow code. +diff --git a/js/src/jit-test/tests/regexp/bug1445907.js b/js/src/jit-test/tests/regexp/bug1445907.js +new file mode 100644 +--- /dev/null ++++ b/js/src/jit-test/tests/regexp/bug1445907.js +@@ -0,0 +1,15 @@ ++// On ARM64, we failed to save x28 properly when generating code for the regexp ++// matcher. ++// ++// There's wasm and Debugger code here because the combination forces the use of ++// x28 and exposes the bug when running on the simulator. ++ ++if (!wasmIsSupported()) ++ quit(); ++ ++var g = newGlobal(''); ++var dbg = new Debugger(g); ++g.eval(`var m = new WebAssembly.Instance(new WebAssembly.Module(wasmTextToBinary('(module (func (export "test")))')))`); ++var re = /./; ++dbg.onEnterFrame = function(frame) { re.exec("x") }; ++result = g.eval("m.exports.test()"); + +-- +2.21.0 + |