diff --git a/lld/MachO/SyntheticSections.cpp b/lld/MachO/SyntheticSections.cpp --- a/lld/MachO/SyntheticSections.cpp +++ b/lld/MachO/SyntheticSections.cpp @@ -360,6 +360,23 @@ if (i == opcodes.size()) opcodes[pWrite] = opcodes[i - 1]; opcodes.resize(pWrite + 1); + + // Pass 3: Use immediate encodings + // Every binding is the size of one pointer. If the next binding is a + // multiple of wordSize away that is within BIND_IMMEDIATE_MASK, the + // opcode can be scaled by wordSize into a single byte and dyld will + // expand it to the correct address. + for (auto &p : opcodes) { + // It's unclear why the check needs to be less than BIND_IMMEDIATE_MASK, + // but ld64 currently does this. This could be a potential bug, but + // for now, perform the same behavior to prevent mysterious bugs. + if ((p.opcode == BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB) && + ((p.data / target->wordSize) < BIND_IMMEDIATE_MASK) && + ((p.data % target->wordSize) == 0)) { + p.opcode = BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED; + p.data /= target->wordSize; + } + } } static void flushOpcodes(const BindIR &op, raw_svector_ostream &os) { @@ -383,6 +400,9 @@ encodeULEB128(op.consecutiveCount, os); encodeULEB128(op.data, os); break; + case BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED: + os << static_cast(op.opcode | op.data); + break; default: llvm_unreachable("cannot bind to an unrecognized symbol"); } diff --git a/lld/test/MachO/bind-opcodes.s b/lld/test/MachO/bind-opcodes.s --- a/lld/test/MachO/bind-opcodes.s +++ b/lld/test/MachO/bind-opcodes.s @@ -1,15 +1,16 @@ -# REQUIRES: x86 +# REQUIRES: x86, arm # RUN: rm -rf %t; split-file %s %t # RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/foo.s -o %t/foo.o -# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin %t/test.s -o %t/test.o +# RUN: llvm-mc -filetype=obj -triple=x86_64-apple-darwin --defsym PTR64=0 %t/test.s -o %t/test.o # RUN: %lld -O2 -dylib %t/foo.o -o %t/libfoo.dylib -# RUN: %lld -O2 -lSystem %t/test.o %t/libfoo.dylib -o %t/test +# RUN: %lld -O2 -lSystem %t/test.o %t/libfoo.dylib -o %t/test-x86_64 -## Test: +## Test (64-bit): ## 1/ We emit exactly one BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM per symbol. ## 2/ Combine BIND_OPCODE_DO_BIND and BIND_OPCODE_ADD_ADDR_ULEB pairs. ## 3/ Compact BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB -# RUN: obj2yaml %t/test | FileCheck %s +## 4/ Use BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED if possible. +# RUN: obj2yaml %t/test-x86_64 | FileCheck %s # CHECK: BindOpcodes: # CHECK-NEXT: Opcode: BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM @@ -54,9 +55,8 @@ # CHECK-NEXT: Imm: 0 # CHECK-NEXT: ULEBExtraData: [ 0xFFFFFFFFFFFFEFD0 ] # CHECK-NEXT: Symbol: '' -# CHECK-NEXT: Opcode: BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB -# CHECK-NEXT: Imm: 0 -# CHECK-NEXT: ULEBExtraData: [ 0x8 ] +# CHECK-NEXT: Opcode: BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED +# CHECK-NEXT: Imm: 1 # CHECK-NEXT: Symbol: '' # CHECK-NEXT: Opcode: BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB # CHECK-NEXT: Imm: 0 @@ -69,16 +69,86 @@ # CHECK-NEXT: Imm: 0 # CHECK-NEXT: Symbol: '' -# RUN: llvm-objdump --macho --bind %t/test | FileCheck %s --check-prefix=BIND +# RUN: llvm-mc -filetype=obj -triple=arm64_32-apple-darwin %t/foo.s -o %t/foo.o +# RUN: llvm-mc -filetype=obj -triple=arm64_32-apple-darwin --defsym PTR32=0 %t/test.s -o %t/test.o +# RUN: %lld -arch arm64_32 -O2 -dylib %t/foo.o -o %t/libfoo.dylib +# RUN: %lld -arch arm64_32 -O2 -dylib %t/test.o %t/libfoo.dylib -o %t/libtest-arm64_32.dylib + +## Test (32-bit): +## 1/ We emit exactly one BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM per symbol. +## 2/ Combine BIND_OPCODE_DO_BIND and BIND_OPCODE_ADD_ADDR_ULEB pairs. +## 3/ Compact BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB +## 4/ Use BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED if possible. +# RUN: obj2yaml %t/libtest-arm64_32.dylib | FileCheck %s --check-prefix=CHECK32 + +# CHECK32: BindOpcodes: +# CHECK32-NEXT: Opcode: BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: Symbol: _foo +# CHECK32-NEXT: Opcode: BIND_OPCODE_SET_TYPE_IMM +# CHECK32-NEXT: Imm: 1 +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_SET_DYLIB_ORDINAL_IMM +# CHECK32-NEXT: Imm: 1 +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_SET_SEGMENT_AND_OFFSET_ULEB +# CHECK32-NEXT: Imm: 1 +# CHECK32-NEXT: ULEBExtraData: [ 0x0 ] +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_DO_BIND_ULEB_TIMES_SKIPPING_ULEB +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: ULEBExtraData: [ 0x2, 0x4 ] +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_SET_ADDEND_SLEB +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: SLEBExtraData: [ 1 ] +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: ULEBExtraData: [ 0x1004 ] +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_SET_ADDEND_SLEB +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: SLEBExtraData: [ 0 ] +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_DO_BIND +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_SET_SYMBOL_TRAILING_FLAGS_IMM +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: Symbol: _bar +# CHECK32-NEXT: Opcode: BIND_OPCODE_SET_TYPE_IMM +# CHECK32-NEXT: Imm: 1 +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_ADD_ADDR_ULEB +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: ULEBExtraData: [ 0xFFFFFFFFFFFFEFE8 ] +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_DO_BIND_ADD_ADDR_IMM_SCALED +# CHECK32-NEXT: Imm: 1 +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_DO_BIND_ADD_ADDR_ULEB +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: ULEBExtraData: [ 0x1004 ] +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_DO_BIND +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: Symbol: '' +# CHECK32-NEXT: Opcode: BIND_OPCODE_DONE +# CHECK32-NEXT: Imm: 0 +# CHECK32-NEXT: Symbol: '' + +# RUN: llvm-objdump --macho --bind %t/test-x86_64 | FileCheck %s -D#PTR=8 --check-prefix=BIND +# RUN: llvm-objdump --macho --bind %t/libtest-arm64_32.dylib | FileCheck %s -D#PTR=4 --check-prefix=BIND # BIND: Bind table: -# BIND-NEXT: segment section address type addend dylib symbol -# BIND-NEXT: __DATA __data 0x100001000 pointer 0 libfoo _foo -# BIND-NEXT: __DATA __data 0x100001010 pointer 0 libfoo _foo -# BIND-NEXT: __DATA __data 0x100001020 pointer 1 libfoo _foo -# BIND-NEXT: __DATA __data 0x100002030 pointer 0 libfoo _foo -# BIND-NEXT: __DATA __data 0x100001008 pointer 0 libfoo _bar -# BIND-NEXT: __DATA __data 0x100001018 pointer 0 libfoo _bar -# BIND-NEXT: __DATA __data 0x100002028 pointer 0 libfoo _bar +# BIND-NEXT: segment section address type addend dylib symbol +# BIND-NEXT: __DATA __data 0x[[#%X,DATA:]] pointer 0 libfoo _foo +# BIND-NEXT: __DATA __data 0x[[#%.8X,DATA + mul(PTR, 2)]] pointer 0 libfoo _foo +# BIND-NEXT: __DATA __data 0x[[#%.8X,DATA + mul(PTR, 4)]] pointer 1 libfoo _foo +# BIND-NEXT: __DATA __data 0x[[#%.8X,DATA + 4096 + mul(PTR, 6)]] pointer 0 libfoo _foo +# BIND-NEXT: __DATA __data 0x[[#%.8X,DATA + PTR]] pointer 0 libfoo _bar +# BIND-NEXT: __DATA __data 0x[[#%.8X,DATA + mul(PTR, 3)]] pointer 0 libfoo _bar +# BIND-NEXT: __DATA __data 0x[[#%.8X,DATA + 4096 + mul(PTR, 5)]] pointer 0 libfoo _bar # BIND-EMPTY: #--- foo.s @@ -89,15 +159,27 @@ .space 4 #--- test.s +.ifdef PTR64 +.macro ptr val + .quad \val +.endm +.endif + +.ifdef PTR32 +.macro ptr val + .int \val +.endm +.endif + .data -.quad _foo -.quad _bar -.quad _foo -.quad _bar -.quad _foo+1 +ptr _foo +ptr _bar +ptr _foo +ptr _bar +ptr _foo+1 .zero 0x1000 -.quad _bar -.quad _foo +ptr _bar +ptr _foo .globl _main .text