ipra-local-linkage.ll
1.02 KB
; RUN: llc < %s | FileCheck %s -check-prefix=NOIPRA
; RUN: llc -enable-ipra < %s | FileCheck %s
target triple = "x86_64--"
define internal void @foo() norecurse {
; When IPRA is not enabled R15 will be saved by foo as it is callee saved reg.
; NOIPRA-LABEL: foo:
; NOIPRA: pushq %r15
; When IPRA is enabled none register should be saved as foo() is local function
; so we optimize it to save no registers.
; CHECK-LABEL: foo:
; CHECK-NOT: pushq %r15
call void asm sideeffect "movl %r14d, %r15d", "~{r15}"()
ret void
}
define void @bar(i32 %X) {
call void asm sideeffect "movl %r12d, $0", "{r15}~{r12}"(i32 %X)
; As R15 is clobbered by foo() when IPRA is enabled value of R15 should be
; saved if register containing orignal value is also getting clobbered
; and reloaded after foo(), here original value is loaded back into R15D after
; call to foo.
call void @foo()
; CHECK-LABEL: bar:
; CHECK: callq foo
; CHECK-NEXT: movl %edi, %r15d
call void asm sideeffect "movl $0, %r12d", "{r15}~{r12}"(i32 %X)
ret void
}