1 ; RUN: llc < %s -march=x86-64 -mtriple=x86_64-linux-gnu -relocation-model=pic | FileCheck %s 2 3 @x = internal thread_local global i32 0, align 4 4 @y = internal thread_local global i32 0, align 4 5 6 ; get_x and get_y are here to prevent x and y to be optimized away as 0 7 8 define i32* @get_x() { 9 entry: 10 ret i32* @x 11 ; FIXME: This function uses a single thread-local variable, 12 ; so we might want to fall back to general-dynamic here. 13 ; CHECK-LABEL: get_x: 14 ; CHECK: leaq x@TLSLD(%rip), %rdi 15 ; CHECK-NEXT: callq __tls_get_addr@PLT 16 ; CHECK: x@DTPOFF 17 } 18 19 define i32* @get_y() { 20 entry: 21 ret i32* @y 22 } 23 24 define i32 @f(i32 %i) { 25 entry: 26 %cmp = icmp eq i32 %i, 1 27 br i1 %cmp, label %return, label %if.else 28 ; This bb does not access TLS, so should not call __tls_get_addr. 29 ; CHECK-LABEL: f: 30 ; CHECK-NOT: __tls_get_addr 31 ; CHECK: je 32 33 34 if.else: 35 %0 = load i32, i32* @x, align 4 36 %cmp1 = icmp eq i32 %i, 2 37 br i1 %cmp1, label %if.then2, label %return 38 ; Now we call __tls_get_addr. 39 ; CHECK: # %if.else 40 ; CHECK: leaq x@TLSLD(%rip), %rdi 41 ; CHECK-NEXT: callq __tls_get_addr@PLT 42 ; CHECK: x@DTPOFF 43 44 45 if.then2: 46 %1 = load i32, i32* @y, align 4 47 %add = add nsw i32 %1, %0 48 br label %return 49 ; This accesses TLS, but is dominated by the previous block, 50 ; so should not have to call __tls_get_addr again. 51 ; CHECK: # %if.then2 52 ; CHECK-NOT: __tls_get_addr 53 ; CHECK: y@DTPOFF 54 55 56 return: 57 %retval.0 = phi i32 [ %add, %if.then2 ], [ 5, %entry ], [ %0, %if.else ] 58 ret i32 %retval.0 59 } 60
