; RUN: llc < %s -mtriple=x86_64-linux | FileCheck %s --check-prefix=CHECK ; Test how we handle pathologically large stack frames when RAX is live through ; the prologue and epilogue. declare void @bar(ptr) declare void @llvm.va_start(ptr) ; For stack frames between 2GB and 16GB, do multiple adjustments. define i32 @stack_frame_8gb(i32 %x, ...) nounwind { ; CHECK-LABEL: stack_frame_8gb: ; CHECK: subq ${{.*}}, %rsp # imm = 0x7FFFFFFF ; CHECK: subq ${{.*}}, %rsp # imm = 0x7FFFFFFF ; CHECK: subq ${{.*}}, %rsp # imm = 0x7FFFFFFF ; CHECK: subq ${{.*}}, %rsp # imm = 0x7FFFFFFF ; CHECK: subq ${{.*}}, %rsp ; CHECK: callq bar ; CHECK: addq ${{.*}}, %rsp # imm = 0x7FFFFFFF ; CHECK: addq ${{.*}}, %rsp # imm = 0x7FFFFFFF ; CHECK: addq ${{.*}}, %rsp # imm = 0x7FFFFFFF ; CHECK: addq ${{.*}}, %rsp # imm = 0x7FFFFFFF ; CHECK: addq ${{.*}}, %rsp ; CHECK: retq %1 = alloca [u0x200000000 x i8] %va = alloca i8, i32 24 call void @llvm.va_start(ptr %va) call void @bar(ptr %1) ret i32 %x } ; For stack frames larger than 16GB, spill EAX instead of doing a linear number ; of adjustments. ; This function should have a frame size of 0x4000000D0. The 0xD0 is 208 bytes ; from 24 bytes of va_list, 176 bytes of spilled varargs regparms, and 8 bytes ; of alignment. We subtract 8 less and add 8 more in the prologue and epilogue ; respectively to account for the PUSH. define i32 @stack_frame_16gb(i32 %x, ...) nounwind { ; CHECK-LABEL: stack_frame_16gb: ; CHECK: pushq %rax ; CHECK-NEXT: movabsq ${{.*}}, %rax # imm = 0xFFFFFFFBFFFFFF38 ; CHECK-NEXT: addq %rsp, %rax ; CHECK-NEXT: xchgq %rax, (%rsp) ; CHECK-NEXT: movq (%rsp), %rsp ; CHECK: callq bar ; CHECK: pushq %rax ; CHECK-NEXT: movabsq ${{.*}}, %rax # imm = 0x4000000D8 ; CHECK-NEXT: addq %rsp, %rax ; CHECK-NEXT: xchgq %rax, (%rsp) ; CHECK-NEXT: movq (%rsp), %rsp ; CHECK: retq %1 = alloca [u0x400000000 x i8] %va = alloca i8, i32 24 call void @llvm.va_start(ptr %va) call void @bar(ptr %1) ret i32 %x }