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; RUN: llc < %s -march=x86-64 -mtriple=x86_64-linux-gnu -relocation-model=pic | FileCheck %s
@x = internal thread_local global i32 0, align 4
@y = internal thread_local global i32 0, align 4
; get_x and get_y are here to prevent x and y to be optimized away as 0
define i32* @get_x() {
entry:
ret i32* @x
; FIXME: This function uses a single thread-local variable,
; so we might want to fall back to general-dynamic here.
; CHECK-LABEL: get_x:
; CHECK: leaq x@TLSLD(%rip), %rdi
; CHECK-NEXT: callq __tls_get_addr@PLT
; CHECK: x@DTPOFF
}
define i32* @get_y() {
entry:
ret i32* @y
}
define i32 @f(i32 %i) {
entry:
%cmp = icmp eq i32 %i, 1
br i1 %cmp, label %return, label %if.else
; This bb does not access TLS, so should not call __tls_get_addr.
; CHECK-LABEL: f:
; CHECK-NOT: __tls_get_addr
; CHECK: je
if.else:
%0 = load i32* @x, align 4
%cmp1 = icmp eq i32 %i, 2
br i1 %cmp1, label %if.then2, label %return
; Now we call __tls_get_addr.
; CHECK: # %if.else
; CHECK: leaq x@TLSLD(%rip), %rdi
; CHECK-NEXT: callq __tls_get_addr@PLT
; CHECK: x@DTPOFF
if.then2:
%1 = load i32* @y, align 4
%add = add nsw i32 %1, %0
br label %return
; This accesses TLS, but is dominated by the previous block,
; so should not have to call __tls_get_addr again.
; CHECK: # %if.then2
; CHECK-NOT: __tls_get_addr
; CHECK: y@DTPOFF
return:
%retval.0 = phi i32 [ %add, %if.then2 ], [ 5, %entry ], [ %0, %if.else ]
ret i32 %retval.0
}
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