tailcall-largecode.ll
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; RUN: llc < %s -mtriple=x86_64-linux-gnu -tailcallopt -code-model=large -enable-misched=false | FileCheck %s
declare fastcc i32 @callee(i32 %arg)
define fastcc i32 @directcall(i32 %arg) {
entry:
; This is the large code model, so &callee may not fit into the jmp
; instruction. Instead, stick it into a register.
; CHECK: movabsq $callee, [[REGISTER:%r[a-z0-9]+]]
; CHECK: jmpq *[[REGISTER]] # TAILCALL
%res = tail call fastcc i32 @callee(i32 %arg)
ret i32 %res
}
; Check that the register used for an indirect tail call doesn't
; clobber any of the arguments.
define fastcc i32 @indirect_manyargs(i32(i32,i32,i32,i32,i32,i32,i32)* %target) {
; Adjust the stack to enter the function. (The amount of the
; adjustment may change in the future, in which case the location of
; the stack argument and the return adjustment will change too.)
; CHECK: pushq
; Put the call target into R11, which won't be clobbered while restoring
; callee-saved registers and won't be used for passing arguments.
; CHECK: movq %rdi, %rax
; Pass the stack argument.
; CHECK: movl $7, 16(%rsp)
; Pass the register arguments, in the right registers.
; CHECK: movl $1, %edi
; CHECK: movl $2, %esi
; CHECK: movl $3, %edx
; CHECK: movl $4, %ecx
; CHECK: movl $5, %r8d
; CHECK: movl $6, %r9d
; Adjust the stack to "return".
; CHECK: popq
; And tail-call to the target.
; CHECK: jmpq *%rax # TAILCALL
%res = tail call fastcc i32 %target(i32 1, i32 2, i32 3, i32 4, i32 5,
i32 6, i32 7)
ret i32 %res
}
; Check that the register used for a direct tail call doesn't clobber
; any of the arguments.
declare fastcc i32 @manyargs_callee(i32,i32,i32,i32,i32,i32,i32)
define fastcc i32 @direct_manyargs() {
; Adjust the stack to enter the function. (The amount of the
; adjustment may change in the future, in which case the location of
; the stack argument and the return adjustment will change too.)
; CHECK: pushq
; Pass the stack argument.
; CHECK: movl $7, 16(%rsp)
; This is the large code model, so &manyargs_callee may not fit into
; the jmp instruction. Put it into a register which won't be clobbered
; while restoring callee-saved registers and won't be used for passing
; arguments.
; CHECK: movabsq $manyargs_callee, %rax
; Pass the register arguments, in the right registers.
; CHECK: movl $1, %edi
; CHECK: movl $2, %esi
; CHECK: movl $3, %edx
; CHECK: movl $4, %ecx
; CHECK: movl $5, %r8d
; CHECK: movl $6, %r9d
; Adjust the stack to "return".
; CHECK: popq
; And tail-call to the target.
; CHECK: jmpq *%rax # TAILCALL
%res = tail call fastcc i32 @manyargs_callee(i32 1, i32 2, i32 3, i32 4,
i32 5, i32 6, i32 7)
ret i32 %res
}