// address.
const unsigned X86_64_TrampolineLength = 6;
- // List of x86-64 GPRs to save.
- std::array<const char *, 11> GPRs = {{
- "rbx", "r12", "r13", "r14", "r15", // Callee saved (rbp preserved below).
- "rdi", "rsi", "rdx", "rcx", "r8", "r9", // Int args.
+ // List of x86-64 GPRs to save. Note - RBP saved separately below.
+ std::array<const char *, 14> GPRs = {{
+ "rax", "rbx", "rcx", "rdx",
+ "rsi", "rdi", "r8", "r9",
+ "r10", "r11", "r12", "r13",
+ "r14", "r15"
}};
// Address of the executeCompileCallback function.
AsmStream << " pushq %" << GPR << "\n";
// Store floating-point state with FXSAVE.
- AsmStream << " subq $512, %rsp\n"
+ // Note: We need to keep the stack 16-byte aligned, so if we've emitted an odd
+ // number of 64-bit pushes so far (GPRs.size() plus 1 for RBP) then add
+ // an extra 64 bits of padding to the FXSave area.
+ unsigned Padding = (GPRs.size() + 1) % 2 ? 8 : 0;
+ unsigned FXSaveSize = 512 + Padding;
+ AsmStream << " subq $" << FXSaveSize << ", %rsp\n"
<< " fxsave (%rsp)\n"
// Load callback manager address, compute trampoline address, call JIT.
// Restore the floating point state.
<< " fxrstor (%rsp)\n"
- << " addq $512, %rsp\n";
+ << " addq $" << FXSaveSize << ", %rsp\n";
for (const auto &GPR : make_range(GPRs.rbegin(), GPRs.rend()))
AsmStream << " popq %" << GPR << "\n";