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1; RUN: llc < %s -mtriple=x86_64-linux -verify-machineinstrs | FileCheck %s --check-prefix=CHECK2 3; Test how we handle pathologically large stack frames when RAX is live through4; the prologue and epilogue.5 6declare void @bar(ptr)7declare void @llvm.va_start(ptr)8 9; For stack frames between 2GB and 16GB, do multiple adjustments.10 11define i32 @stack_frame_8gb(i32 %x, ...) nounwind {12; CHECK-LABEL: stack_frame_8gb:13; CHECK: subq ${{.*}}, %rsp # imm = 0x7FFFFFFF14; CHECK: subq ${{.*}}, %rsp # imm = 0x7FFFFFFF15; CHECK: subq ${{.*}}, %rsp # imm = 0x7FFFFFFF16; CHECK: subq ${{.*}}, %rsp # imm = 0x7FFFFFFF17; CHECK: subq ${{.*}}, %rsp18; CHECK: callq bar19; CHECK: addq ${{.*}}, %rsp # imm = 0x7FFFFFFF20; CHECK: addq ${{.*}}, %rsp # imm = 0x7FFFFFFF21; CHECK: addq ${{.*}}, %rsp # imm = 0x7FFFFFFF22; CHECK: addq ${{.*}}, %rsp # imm = 0x7FFFFFFF23; CHECK: addq ${{.*}}, %rsp24; CHECK: retq25 %1 = alloca [u0x200000000 x i8]26 %va = alloca i8, i32 2427 call void @llvm.va_start(ptr %va)28 call void @bar(ptr %1)29 ret i32 %x30}31 32; For stack frames larger than 16GB, spill EAX instead of doing a linear number33; of adjustments.34 35; This function should have a frame size of 0x4000000D0. The 0xD0 is 208 bytes36; from 24 bytes of va_list, 176 bytes of spilled varargs regparms, and 8 bytes37; of alignment. We subtract 8 less and add 8 more in the prologue and epilogue38; respectively to account for the PUSH.39 40define i32 @stack_frame_16gb(i32 %x, ...) nounwind {41; CHECK-LABEL: stack_frame_16gb:42; CHECK: pushq %rax43; CHECK-NEXT: movabsq ${{.*}}, %rax # imm = 0xFFFFFFFBFFFFFF3844; CHECK-NEXT: addq %rsp, %rax45; CHECK-NEXT: xchgq %rax, (%rsp)46; CHECK-NEXT: movq (%rsp), %rsp47; CHECK: callq bar48; CHECK: pushq %rax49; CHECK-NEXT: movabsq ${{.*}}, %rax # imm = 0x4000000D850; CHECK-NEXT: addq %rsp, %rax51; CHECK-NEXT: xchgq %rax, (%rsp)52; CHECK-NEXT: movq (%rsp), %rsp53; CHECK: retq54 %1 = alloca [u0x400000000 x i8]55 %va = alloca i8, i32 2456 call void @llvm.va_start(ptr %va)57 call void @bar(ptr %1)58 ret i32 %x59}60 61