diff --git a/lld/ELF/Thunks.cpp b/lld/ELF/Thunks.cpp index 07289d0efdf1..97150f99c4cd 100644 --- a/lld/ELF/Thunks.cpp +++ b/lld/ELF/Thunks.cpp @@ -160,16 +160,17 @@ bool ThumbV7ABSLongThunk::isCompatibleWith(uint32_t RelocType) const { void ARMV7PILongThunk::writeTo(uint8_t *Buf, ThunkSection &IS) const { const uint8_t Data[] = { - 0xf0, 0xcf, 0x0f, 0xe3, // P: movw ip,:lower16:S - (P + (L1-P) +8) - 0x00, 0xc0, 0x40, 0xe3, // movt ip,:upper16:S - (P + (L1-P+4) +8) + 0xf0, 0xcf, 0x0f, 0xe3, // P: movw ip,:lower16:S - (P + (L1-P) + 8) + 0x00, 0xc0, 0x40, 0xe3, // movt ip,:upper16:S - (P + (L1-P) + 8) 0x0f, 0xc0, 0x8c, 0xe0, // L1: add ip, ip, pc 0x1c, 0xff, 0x2f, 0xe1, // bx r12 }; uint64_t S = getARMThunkDestVA(Destination); uint64_t P = ThunkSym->getVA(); + uint64_t Offset = S - P - 16; memcpy(Buf, Data, sizeof(Data)); - Target->relocateOne(Buf, R_ARM_MOVW_PREL_NC, S - P - 16); - Target->relocateOne(Buf + 4, R_ARM_MOVT_PREL, S - P - 12); + Target->relocateOne(Buf, R_ARM_MOVW_PREL_NC, Offset); + Target->relocateOne(Buf + 4, R_ARM_MOVT_PREL, Offset); } void ARMV7PILongThunk::addSymbols(ThunkSection &IS) { @@ -187,15 +188,16 @@ bool ARMV7PILongThunk::isCompatibleWith(uint32_t RelocType) const { void ThumbV7PILongThunk::writeTo(uint8_t *Buf, ThunkSection &IS) const { const uint8_t Data[] = { 0x4f, 0xf6, 0xf4, 0x7c, // P: movw ip,:lower16:S - (P + (L1-P) + 4) - 0xc0, 0xf2, 0x00, 0x0c, // movt ip,:upper16:S - (P + (L1-P+4) + 4) + 0xc0, 0xf2, 0x00, 0x0c, // movt ip,:upper16:S - (P + (L1-P) + 4) 0xfc, 0x44, // L1: add r12, pc 0x60, 0x47, // bx r12 }; uint64_t S = getARMThunkDestVA(Destination); uint64_t P = ThunkSym->getVA() & ~0x1; + uint64_t Offset = S - P - 12; memcpy(Buf, Data, sizeof(Data)); - Target->relocateOne(Buf, R_ARM_THM_MOVW_PREL_NC, S - P - 12); - Target->relocateOne(Buf + 4, R_ARM_THM_MOVT_PREL, S - P - 8); + Target->relocateOne(Buf, R_ARM_THM_MOVW_PREL_NC, Offset); + Target->relocateOne(Buf + 4, R_ARM_THM_MOVT_PREL, Offset); } void ThumbV7PILongThunk::addSymbols(ThunkSection &IS) { diff --git a/lld/test/ELF/arm-thunk-edgecase.s b/lld/test/ELF/arm-thunk-edgecase.s new file mode 100644 index 000000000000..81837c7b3284 --- /dev/null +++ b/lld/test/ELF/arm-thunk-edgecase.s @@ -0,0 +1,37 @@ +// REQUIRES: arm +// RUN: llvm-mc -filetype=obj -triple=armv7a-none-linux-gnueabi %s -o %t.o +// RUN: echo "SECTIONS { \ +// RUN: .text_armfunc 0x1000 : { *(.text_armfunc) } \ +// RUN: .text_thumbfunc 0x11010 : { *(.text_thumbfunc) } \ +// RUN: }" > %tarm_to_thumb.script +// RUN: echo "SECTIONS { \ +// RUN: .text_thumbfunc 0x1000 : { *(.text_thumbfunc) } \ +// RUN: .text_armfunc 0x1100c : { *(.text_armfunc) } \ +// RUN: }" > %tthumb_to_arm.script +// RUN: ld.lld -shared -Bsymbolic -script %tarm_to_thumb.script %t.o -o %tarm_to_thumb.so +// RUN: ld.lld -shared -Bsymbolic -script %tthumb_to_arm.script %t.o -o %tthumb_to_arm.so +// RUN: llvm-objdump -triple=armv7a-none-linux-gnueabi -d %tarm_to_thumb.so | FileCheck -check-prefix=ARM-TO-THUMB %s +// RUN: llvm-objdump -triple=thumbv7a-none-linux-gnueabi -d %tthumb_to_arm.so | FileCheck -check-prefix=THUMB-TO-ARM %s + +.syntax unified + +.arm +.section .text_armfunc, "ax", %progbits +.globl armfunc +armfunc: + b thumbfunc + +.thumb +.section .text_thumbfunc, "ax", %progbits +.globl thumbfunc +.thumb_func +thumbfunc: + b.w armfunc + +// ARM-TO-THUMB: __ARMV7PILongThunk_thumbfunc: +// ARM-TO-THUMB-NEXT: 1004: fd cf 0f e3 movw r12, #65533 +// ARM-TO-THUMB-NEXT: 1008: 00 c0 40 e3 movt r12, #0 + +// THUMB-TO-ARM: __ThumbV7PILongThunk_armfunc: +// THUMB-TO-ARM-NEXT: 1004: 4f f6 fc 7c movw r12, #65532 +// THUMB-TO-ARM-NEXT: 1008: c0 f2 00 0c movt r12, #0