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Differential D54620

[MSP430] Use R_MSP430_16_BYTE type for FK_Data_2 fixup
ClosedPublic

Authored by krisb on Nov 16 2018, 2:17 AM.

Details

Reviewers
asl
Commits
rG883c70959d47: [MSP430] Use R_MSP430_16_BYTE type for FK_Data_2 fixup
rL347074: [MSP430] Use R_MSP430_16_BYTE type for FK_Data_2 fixup
Summary

Linker fails to link example like this (simplified case from newlib
sources):

$ cat test.c

extern const char _ctype_b[];
struct _t { char *ptr; };
struct _t T = { ((char *) _ctype_b + 3) };

$ cat ctype.c

char _ctype_b[4] = { 0, 0, 0, 0 };

LD: test.o:(.data+0x0): warning: internal error: unsupported relocation error

We also follow gnu toolchain here, where 2-byte relocation mapped to
R_MSP430_16_BYTE, instead of R_MSP430_16.

Diff Detail

Event Timeline

krisb created this revision.Nov 16 2018, 2:17 AM
Herald added a subscriber: llvm-commits. · View Herald TranscriptNov 16 2018, 2:17 AM
Harbormaster completed remote builds in B25084: Diff 174343.Nov 16 2018, 2:18 AM
asl accepted this revision.Nov 16 2018, 11:23 AM
This revision is now accepted and ready to land.Nov 16 2018, 11:23 AM
Closed by commit rL347074: [MSP430] Use R_MSP430_16_BYTE type for FK_Data_2 fixup (authored by asl). · Explain WhyNov 16 2018, 11:24 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
lib/
Target/
MSP430/
MCTargetDesc/
2 lines
test/
MC/
MSP430/
5 lines

Diff 174343

lib/Target/MSP430/MCTargetDesc/MSP430ELFObjectWriter.cpp

Show All 28 Linespublic:
~MSP430ELFObjectWriter() override {} ~MSP430ELFObjectWriter() override {}
protected: protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target, unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override { const MCFixup &Fixup, bool IsPCRel) const override {
// Translate fixup kind to ELF relocation type. // Translate fixup kind to ELF relocation type.
switch ((unsigned)Fixup.getKind()) { switch ((unsigned)Fixup.getKind()) {
case FK_Data_1: return ELF::R_MSP430_8; case FK_Data_1: return ELF::R_MSP430_8;
case FK_Data_2: return ELF::R_MSP430_16; case FK_Data_2: return ELF::R_MSP430_16_BYTE;
case FK_Data_4: return ELF::R_MSP430_32; case FK_Data_4: return ELF::R_MSP430_32;
case MSP430::fixup_32: return ELF::R_MSP430_32; case MSP430::fixup_32: return ELF::R_MSP430_32;
case MSP430::fixup_10_pcrel: return ELF::R_MSP430_10_PCREL; case MSP430::fixup_10_pcrel: return ELF::R_MSP430_10_PCREL;
case MSP430::fixup_16: return ELF::R_MSP430_16; case MSP430::fixup_16: return ELF::R_MSP430_16;
case MSP430::fixup_16_pcrel: return ELF::R_MSP430_16_PCREL; case MSP430::fixup_16_pcrel: return ELF::R_MSP430_16_PCREL;
case MSP430::fixup_16_byte: return ELF::R_MSP430_16_BYTE; case MSP430::fixup_16_byte: return ELF::R_MSP430_16_BYTE;
case MSP430::fixup_16_pcrel_byte: return ELF::R_MSP430_16_PCREL_BYTE; case MSP430::fixup_16_pcrel_byte: return ELF::R_MSP430_16_PCREL_BYTE;
case MSP430::fixup_2x_pcrel: return ELF::R_MSP430_2X_PCREL; case MSP430::fixup_2x_pcrel: return ELF::R_MSP430_2X_PCREL;
Show All 14 Lines

test/MC/MSP430/reloc.s

Show All 14 Lines; CHECK: ; fixup A - offset: 2, value: disp+2, kind: fixup_16
mov disp, disp+2 mov disp, disp+2
; CHECK: mov disp, disp+2 ; encoding: [0x90,0x40,A,A,B,B] ; CHECK: mov disp, disp+2 ; encoding: [0x90,0x40,A,A,B,B]
; CHECK: ; fixup A - offset: 2, value: disp, kind: fixup_16_pcrel_byte ; CHECK: ; fixup A - offset: 2, value: disp, kind: fixup_16_pcrel_byte
; CHECK: ; fixup B - offset: 4, value: disp+2, kind: fixup_16_pcrel_byte ; CHECK: ; fixup B - offset: 4, value: disp+2, kind: fixup_16_pcrel_byte
jmp foo jmp foo
; CHECK: jmp foo ; encoding: [A,0b001111AA] ; CHECK: jmp foo ; encoding: [A,0b001111AA]
; CHECK: ; fixup A - offset: 0, value: foo, kind: fixup_10_pcrel ; CHECK: ; fixup A - offset: 0, value: foo, kind: fixup_10_pcrel
; RUN: llvm-mc -filetype=obj -triple msp430 < %s | llvm-readobj -r \
; RUN: | FileCheck -check-prefix=RELOC %s
.short _ctype+3
; RELOC: R_MSP430_16_BYTE _ctype 0x3