From fb641d8e566da6cf431398e85faa1254914751ed Mon Sep 17 00:00:00 2001 From: Jacek Caban Date: Mon, 17 Nov 2025 12:44:22 +0100 Subject: [PATCH] [LLD][COFF] Align EC code ranges to page boundaries (#168222) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We already ensure that code for different architectures is always placed in different pages in `assignAddresses`. We represent those ranges using their first and last chunks. However, the RVAs of those chunks may not be page-aligned, for example, due to extra padding for entry-thunk offsets. Align the chunk RVAs to the page boundary so that the emitted ranges correctly include the entire region. This change affects an existing test that checks corner cases triggered by merging a data section into a code section. We may now include such data in the code range. This differs from MSVC’s behavior, but it should not cause practical issues, and the new behavior is arguably more correct. Fixes #168119. (cherry picked from commit af45b0202cdd443beedb02392f653d8cff5bd931) --- lld/COFF/Chunks.cpp | 2 +- lld/test/COFF/arm64ec-codemap.test | 36 +++++++++++++++++++++++++++--- 2 files changed, 34 insertions(+), 4 deletions(-) diff --git a/lld/COFF/Chunks.cpp b/lld/COFF/Chunks.cpp index 01752cdc6a9da..cfb33daa024a7 100644 --- a/lld/COFF/Chunks.cpp +++ b/lld/COFF/Chunks.cpp @@ -939,7 +939,7 @@ void ECCodeMapChunk::writeTo(uint8_t *buf) const { auto table = reinterpret_cast(buf); for (uint32_t i = 0; i < map.size(); i++) { const ECCodeMapEntry &entry = map[i]; - uint32_t start = entry.first->getRVA(); + uint32_t start = entry.first->getRVA() & ~0xfff; table[i].StartOffset = start | entry.type; table[i].Length = entry.last->getRVA() + entry.last->getSize() - start; } diff --git a/lld/test/COFF/arm64ec-codemap.test b/lld/test/COFF/arm64ec-codemap.test index 050261117be2e..bbc682d19920f 100644 --- a/lld/test/COFF/arm64ec-codemap.test +++ b/lld/test/COFF/arm64ec-codemap.test @@ -7,6 +7,7 @@ RUN: llvm-mc -filetype=obj -triple=arm64ec-windows arm64ec-func-sym2.s -o arm64e RUN: llvm-mc -filetype=obj -triple=arm64ec-windows data-sec.s -o data-sec.obj RUN: llvm-mc -filetype=obj -triple=arm64ec-windows data-sec2.s -o data-sec2.obj RUN: llvm-mc -filetype=obj -triple=arm64ec-windows empty-sec.s -o arm64ec-empty-sec.obj +RUN: llvm-mc -filetype=obj -triple=arm64ec-windows entry-thunk.s -o entry-thunk.obj RUN: llvm-mc -filetype=obj -triple=x86_64-windows x86_64-func-sym.s -o x86_64-func-sym.obj RUN: llvm-mc -filetype=obj -triple=x86_64-windows empty-sec.s -o x86_64-empty-sec.obj RUN: llvm-mc -filetype=obj -triple=aarch64-windows %S/Inputs/loadconfig-arm64.s -o loadconfig-arm64.obj @@ -162,15 +163,17 @@ RUN: loadconfig-arm64ec.obj -dll -noentry -merge:test=.testdata -merge: RUN: llvm-readobj --coff-load-config testcm.dll | FileCheck -check-prefix=CODEMAPCM %s CODEMAPCM: CodeMap [ -CODEMAPCM-NEXT: 0x4008 - 0x4016 X64 +CODEMAPCM-NEXT: 0x4000 - 0x4016 X64 CODEMAPCM-NEXT: ] RUN: llvm-objdump -d testcm.dll | FileCheck -check-prefix=DISASMCM %s DISASMCM: Disassembly of section .testdat: DISASMCM-EMPTY: DISASMCM-NEXT: 0000000180004000 <.testdat>: -DISASMCM-NEXT: 180004000: 00000001 udf #0x1 -DISASMCM-NEXT: 180004004: 00000000 udf #0x0 +DISASMCM-NEXT: 180004000: 01 00 addl %eax, (%rax) +DISASMCM-NEXT: 180004002: 00 00 addb %al, (%rax) +DISASMCM-NEXT: 180004004: 00 00 addb %al, (%rax) +DISASMCM-NEXT: 180004006: 00 00 addb %al, (%rax) DISASMCM-NEXT: 180004008: b8 03 00 00 00 movl $0x3, %eax DISASMCM-NEXT: 18000400d: c3 retq DISASMCM-NEXT: 18000400e: 00 00 addb %al, (%rax) @@ -207,6 +210,14 @@ DISASMMS-NEXT: 0000000180006000 : DISASMMS-NEXT: 180006000: 528000a0 mov w0, #0x5 // =5 DISASMMS-NEXT: 180006004: d65f03c0 ret +Test the code map that includes an ARM64EC function padded by its entry-thunk offset. + +RUN: lld-link -out:testpad.dll -machine:arm64ec entry-thunk.obj loadconfig-arm64ec.obj -dll -noentry -include:func +RUN: llvm-readobj --coff-load-config testpad.dll | FileCheck -check-prefix=CODEMAPPAD %s +CODEMAPPAD: CodeMap [ +CODEMAPPAD: 0x1000 - 0x1010 ARM64EC +CODEMAPPAD-NEXT: ] + #--- arm64-func-sym.s .text @@ -266,3 +277,22 @@ x86_64_func_sym2: .section .empty1, "xr" .section .empty2, "xr" .section .empty3, "xr" + +#--- entry-thunk.s + .section .text,"xr",discard,func + .globl func + .p2align 2, 0x0 +func: + mov w0, #1 + ret + + .section .wowthk$aa,"xr",discard,thunk + .globl thunk + .p2align 2 +thunk: + ret + + .section .hybmp$x,"yi" + .symidx func + .symidx thunk + .word 1 // entry thunk