arm-thunk-many-passes.s
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// REQUIRES: arm
// RUN: llvm-mc -arm-add-build-attributes -filetype=obj -triple=armv7a-linux-gnueabihf %s -o %t
// RUN: echo "SECTIONS { \
// RUN: . = SIZEOF_HEADERS; \
// RUN: .text 0x00011000 : { *(.text.*) } \
// RUN: } \
// RUN: sym = .;" > %t.script
// RUN: ld.lld --script %t.script %t -o %t2
// RUN: llvm-readobj --sections --symbols %t2 | FileCheck --check-prefix=CHECK-ELF %s
// RUN: llvm-objdump --no-show-raw-insn --start-address=0x11000 --stop-address=0x1103c -d %t2 | FileCheck %s
// An example of thunk generation that takes the maximum number of permitted
// passes to converge. We start with a set of branches of which all but one are
// in range. Any thunk added to extend the range of a branch is inserted in
// between the branches and the targets which knocks some more branches out
// of range. At the end of 9 passes of createThunks() every branch has a
// range extension thunk, allowing the final pass to check that no more thunks
// are required.
//
// As the size of the .text section changes 9 times, the symbol sym which
// depends on the size of .text will be updated 9 times. This test checks that
// any iteration limit to updating symbols does not limit thunk convergence.
// up to its pass limit without
//
// CHECK-ELF: Name: .text
// CHECK-ELF-NEXT: Type: SHT_PROGBITS
// CHECK-ELF-NEXT: Flags [
// CHECK-ELF-NEXT: SHF_ALLOC
// CHECK-ELF-NEXT: SHF_EXECINSTR
// CHECK-ELF-NEXT: ]
// CHECK-ELF-NEXT: Address: 0x11000
// CHECK-ELF-NEXT: Offset: 0x1000
// CHECK-ELF-NEXT: Size: 16777292
// CHECK-ELF: Name: sym
// CHECK-ELF-NEXT: Value: 0x101104C
// CHECK: 00011000 _start:
// CHECK-NEXT: 11000: b.w #14680132 <__Thumbv7ABSLongThunk_f3>
// CHECK-NEXT: 11004: b.w #14680128 <__Thumbv7ABSLongThunk_f3>
// CHECK-NEXT: 11008: b.w #14680128 <__Thumbv7ABSLongThunk_f4>
// CHECK-NEXT: 1100c: b.w #14680124 <__Thumbv7ABSLongThunk_f4>
// CHECK-NEXT: 11010: b.w #14680124 <__Thumbv7ABSLongThunk_f5>
// CHECK-NEXT: 11014: b.w #14680120 <__Thumbv7ABSLongThunk_f5>
// CHECK-NEXT: 11018: b.w #14680120 <__Thumbv7ABSLongThunk_f6>
// CHECK-NEXT: 1101c: b.w #14680116 <__Thumbv7ABSLongThunk_f6>
// CHECK-NEXT: 11020: b.w #14680116 <__Thumbv7ABSLongThunk_f7>
// CHECK-NEXT: 11024: b.w #14680112 <__Thumbv7ABSLongThunk_f7>
// CHECK-NEXT: 11028: b.w #14680112 <__Thumbv7ABSLongThunk_f8>
// CHECK-NEXT: 1102c: b.w #14680108 <__Thumbv7ABSLongThunk_f8>
// CHECK-NEXT: 11030: b.w #14680108 <__Thumbv7ABSLongThunk_f9>
// CHECK-NEXT: 11034: b.w #14680104 <__Thumbv7ABSLongThunk_f9>
// CHECK-NEXT: 11038: b.w #14680104 <__Thumbv7ABSLongThunk_f10>
.thumb
.section .text.00, "ax", %progbits
.globl _start
.thumb_func
_start: b.w f2
b.w f2
b.w f3
b.w f3
b.w f4
b.w f4
b.w f5
b.w f5
b.w f6
b.w f6
b.w f7
b.w f7
b.w f8
b.w f8
b.w f9
b.w f9
b.w f10
b.w f10
.section .text.01, "ax", %progbits
.space 14 * 1024 * 1024
// Thunks are inserted here, initially only 1 branch is out of range and needs
// a thunk. However the added thunk is 4-bytes in size which makes another
// branch out of range, which adds another thunk ...
.section .text.02, "ax", %progbits
.space (2 * 1024 * 1024) - 68
.thumb_func
f2: bx lr
nop
.thumb_func
f3: bx lr
nop
.thumb_func
f4: bx lr
nop
.thumb_func
f5: bx lr
nop
.thumb_func
f6: bx lr
nop
.thumb_func
f7: bx lr
nop
.thumb_func
f8: bx lr
nop
.thumb_func
f9: bx lr
nop
.thumb_func
f10: bx lr
nop