[PowerPC][LLD] Make sure that the correct Thunks are used.
This fixes an issue where mixed TOC / NOTOC calls can call the incorrect
thunks if a previous thunk already exists. The issue appears when a TOC
funciton calls a NOTOC callee and then a different NOTOC function calls the same
NOTOC callee. In this case the linker would sometimes incorrectly call the
same thunk for both cases.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D101837
diff --git a/lld/ELF/Thunks.cpp b/lld/ELF/Thunks.cpp
index 331c5c8..3d9b651 100644
--- a/lld/ELF/Thunks.cpp
+++ b/lld/ELF/Thunks.cpp
@@ -312,6 +312,8 @@
uint32_t size() override { return getMayUseShortThunk() ? 8 : 32; }
void writeTo(uint8_t *buf) override;
void addSymbols(ThunkSection &isec) override;
+ bool isCompatibleWith(const InputSection &isec,
+ const Relocation &rel) const override;
private:
// Transitioning from long to short can create layout oscillations in
@@ -333,6 +335,8 @@
uint32_t size() override { return 32; }
void writeTo(uint8_t *buf) override;
void addSymbols(ThunkSection &isec) override;
+ bool isCompatibleWith(const InputSection &isec,
+ const Relocation &rel) const override;
};
// PPC64 PC-relative PLT Stub
@@ -965,6 +969,11 @@
s->needsTocRestore = true;
}
+bool PPC64R2SaveStub::isCompatibleWith(const InputSection &isec,
+ const Relocation &rel) const {
+ return rel.type == R_PPC64_REL24 || rel.type == R_PPC64_REL14;
+}
+
void PPC64R12SetupStub::writeTo(uint8_t *buf) {
int64_t offset = destination.getVA() - getThunkTargetSym()->getVA();
if (!isInt<34>(offset))
@@ -995,6 +1004,11 @@
isec);
}
+bool PPC64R12SetupStub::isCompatibleWith(const InputSection &isec,
+ const Relocation &rel) const {
+ return rel.type == R_PPC64_REL24_NOTOC;
+}
+
void PPC64PCRelPLTStub::writeTo(uint8_t *buf) {
int nextInstOffset = 0;
int64_t offset = destination.getGotPltVA() - getThunkTargetSym()->getVA();
diff --git a/lld/test/ELF/ppc64-pcrel-cross-link.s b/lld/test/ELF/ppc64-pcrel-cross-link.s
new file mode 100644
index 0000000..620e113
--- /dev/null
+++ b/lld/test/ELF/ppc64-pcrel-cross-link.s
@@ -0,0 +1,140 @@
+# REQUIRES: ppc
+# RUN: split-file %s %t
+
+# RUN: llvm-mc -filetype=obj -triple=powerpc64le %t/callees.s -o %t-callees.o
+# RUN: llvm-mc -filetype=obj -triple=powerpc64le %t/callertoc.s -o %t-callertoc.o
+# RUN: llvm-mc -filetype=obj -triple=powerpc64le %t/callernotoc.s -o %t-callernotoc.o
+# RUN: ld.lld -T %t/lds %t-callees.o %t-callernotoc.o %t-callertoc.o -o %t-r12setup
+# RUN: ld.lld -T %t/ldsswap %t-callees.o %t-callernotoc.o %t-callertoc.o -o %t-r2save
+
+# RUN: llvm-objdump -d --no-show-raw-insn --mcpu=pwr10 %t-r12setup | \
+# RUN: FileCheck %s --check-prefix=NOSWAP
+# RUN: llvm-objdump -d --no-show-raw-insn --mcpu=pwr10 %t-r2save | \
+# RUN: FileCheck %s --check-prefix=SWAP
+
+## This test checks that it is possible to mix TOC and NOTOC functions and have
+## the correct thunks for all of the calls.
+
+# NOSWAP-LABEL: 01001000 <func>:
+# NOSWAP-NEXT: blr
+# NOSWAP-LABEL: 01002000 <callee_toc>:
+# NOSWAP: bl 0x1001000
+# NOSWAP: blr
+# NOSWAP-LABEL: 01002018 <callee_notoc>:
+# NOSWAP: bl 0x1001000
+# NOSWAP: blr
+# NOSWAP-LABEL: 10030000 <caller_notoc>:
+# NOSWAP-NEXT: bl 0x10030010
+# NOSWAP-NEXT: bl 0x10030030
+# NOSWAP-NEXT: blr
+# NOSWAP-LABEL: 10030010 <__gep_setup_callee_toc>:
+# NOSWAP: bctr
+# NOSWAP-LABEL: 10030030 <__long_branch_pcrel_callee_notoc>:
+# NOSWAP: bctr
+# NOSWAP-LABEL: 10040000 <caller_toc>:
+# NOSWAP: bl 0x10040020
+# NOSWAP-NEXT: nop
+# NOSWAP-NEXT: bl 0x10040040
+# NOSWAP-NEXT: ld 2, 24(1)
+# NOSWAP-NEXT: blr
+# NOSWAP-LABEL: 10040020 <__long_branch_callee_toc>:
+# NOSWAP: bctr
+# NOSWAP-LABEL: 10040040 <__toc_save_callee_notoc>:
+# NOSWAP-NEXT: std 2, 24(1)
+# NOSWAP: bctr
+
+# SWAP-LABEL: 01001000 <func>:
+# SWAP-NEXT: blr
+# SWAP-LABEL: 01002000 <callee_toc>:
+# SWAP: bl 0x1001000
+# SWAP: blr
+# SWAP-LABEL: 01002018 <callee_notoc>:
+# SWAP: bl 0x1001000
+# SWAP: blr
+# SWAP-LABEL: 10030000 <caller_toc>:
+# SWAP: bl 0x10030020
+# SWAP-NEXT: nop
+# SWAP-NEXT: bl 0x10030040
+# SWAP-NEXT: ld 2, 24(1)
+# SWAP-NEXT: blr
+# SWAP-LABEL: 10030020 <__long_branch_callee_toc>:
+# SWAP: bctr
+# SWAP-LABEL: 10030040 <__toc_save_callee_notoc>:
+# SWAP-NEXT: std 2, 24(1)
+# SWAP: bctr
+# SWAP-LABEL: 10040000 <caller_notoc>:
+# SWAP-NEXT: bl 0x10040010
+# SWAP-NEXT: bl 0x10040030
+# SWAP-NEXT: blr
+# SWAP-LABEL: 10040010 <__gep_setup_callee_toc>:
+# SWAP: bctr
+# SWAP-LABEL: 10040030 <__long_branch_pcrel_callee_notoc>:
+# SWAP: bctr
+
+#--- lds
+SECTIONS {
+ .text_func 0x1001000 : { *(.text_func) }
+ .text_callee 0x1002000 : { *(.text_callee) }
+ .text_caller_notoc 0x10030000 : { *(.text_caller_notoc) }
+ .text_caller_toc 0x10040000 : { *(.text_caller_toc) }
+}
+
+#--- ldsswap
+SECTIONS {
+ .text_func 0x1001000 : { *(.text_func) }
+ .text_callee 0x1002000 : { *(.text_callee) }
+ .text_caller_toc 0x10030000 : { *(.text_caller_toc) }
+ .text_caller_notoc 0x10040000 : { *(.text_caller_notoc) }
+}
+
+#--- callees.s
+.section .text_func, "ax", %progbits
+func:
+ blr
+
+.globl callee_toc
+.section .text_callee, "ax", %progbits
+callee_toc:
+.Lfunc_gep1:
+ addis 2, 12, .TOC.-.Lfunc_gep1@ha
+ addi 2, 2, .TOC.-.Lfunc_gep1@l
+.Lfunc_lep1:
+ .localentry callee_toc, .Lfunc_lep1-.Lfunc_gep1
+ bl func
+ addis 4, 2, global@toc@ha
+ lwz 4, global@toc@l(4)
+ blr
+
+.globl callee_notoc
+callee_notoc:
+ .localentry callee_notoc, 1
+ bl func
+ plwz 4, global@pcrel(0), 1
+ blr
+
+## .globl global
+global:
+ .long 0
+ .size global, 4
+
+#--- callernotoc.s
+.section .text_caller_notoc, "ax", %progbits
+caller_notoc:
+ .localentry caller, 1
+ bl callee_toc@notoc
+ bl callee_notoc@notoc
+ blr
+
+#--- callertoc.s
+.section .text_caller_toc, "ax", %progbits
+caller_toc:
+.Lfunc_gep2:
+ addis 2, 12, .TOC.-.Lfunc_gep2@ha
+ addi 2, 2, .TOC.-.Lfunc_gep2@l
+.Lfunc_lep2:
+ .localentry caller_toc, .Lfunc_lep2-.Lfunc_gep2
+ bl callee_toc
+ nop
+ bl callee_notoc
+ nop
+ blr
