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Differential D41163

[LLD] [COFF] Error out if 20 bit thumb branches are out of range
ClosedPublic

Authored by mstorsjo on Dec 13 2017, 2:25 AM.

Details

Reviewers
ruiu
compnerd
Commits
rG94d72b89d663: [COFF] Error out if 20 bit thumb branches are out of range
rLLD320677: [COFF] Error out if 20 bit thumb branches are out of range
rL320677: [COFF] Error out if 20 bit thumb branches are out of range
Summary

This is similar to what was added in SVN r277838 for 24 bit branch instructions.

Diff Detail

Repository
rL LLVM

Event Timeline

mstorsjo created this revision.Dec 13 2017, 2:25 AM
Herald added a subscriber: javed.absar. · View Herald TranscriptDec 13 2017, 2:25 AM
compnerd accepted this revision.Dec 13 2017, 9:44 AM
This revision is now accepted and ready to land.Dec 13 2017, 9:44 AM
ruiu accepted this revision.Dec 13 2017, 12:42 PM

We should use error() instead of fatal() in this case because the error is not caused by corrupted input files. That said, this patch is LGTM because we use fatal() for other relocations in this file.

Closed by commit rL320677: [COFF] Error out if 20 bit thumb branches are out of range (authored by mstorsjo). · Explain WhyDec 14 2017, 12:57 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
lld/
trunk/
COFF/
2 lines
test/
COFF/
Inputs/
2 lines
10 lines

Diff 126908

lld/trunk/COFF/Chunks.cpp

Show First 20 Lines • Show All 123 Lines • ▼ Show 20 Linesvoid applyMOV32T(uint8_t *Off, uint32_t V) {
uint16_t ImmT = readMOV(Off + 4); // read MOVT operand uint16_t ImmT = readMOV(Off + 4); // read MOVT operand
uint32_t Imm = ImmW | (ImmT << 16); uint32_t Imm = ImmW | (ImmT << 16);
V += Imm; // add the immediate offset V += Imm; // add the immediate offset
applyMOV(Off, V); // set MOVW operand applyMOV(Off, V); // set MOVW operand
applyMOV(Off + 4, V >> 16); // set MOVT operand applyMOV(Off + 4, V >> 16); // set MOVT operand
} }
static void applyBranch20T(uint8_t *Off, int32_t V) { static void applyBranch20T(uint8_t *Off, int32_t V) {
if (!isInt<21>(V))
fatal("relocation out of range");
uint32_t S = V < 0 ? 1 : 0; uint32_t S = V < 0 ? 1 : 0;
uint32_t J1 = (V >> 19) & 1; uint32_t J1 = (V >> 19) & 1;
uint32_t J2 = (V >> 18) & 1; uint32_t J2 = (V >> 18) & 1;
or16(Off, (S << 10) | ((V >> 12) & 0x3f)); or16(Off, (S << 10) | ((V >> 12) & 0x3f));
or16(Off + 2, (J1 << 13) | (J2 << 11) | ((V >> 1) & 0x7ff)); or16(Off + 2, (J1 << 13) | (J2 << 11) | ((V >> 1) & 0x7ff));
} }
void applyBranch24T(uint8_t *Off, int32_t V) { void applyBranch24T(uint8_t *Off, int32_t V) {
▲ Show 20 Lines • Show All 394 Lines • Show Last 20 Lines

lld/trunk/test/COFF/Inputs/far-arm-thumb-abs20.s

.global too_far20
too_far20 = 0x501004

lld/trunk/test/COFF/arm-thumb-branch20-error.s

// REQUIRES: arm
// RUN: llvm-mc -filetype=obj -triple=thumbv7a-windows-gnu %s -o %t.obj
// RUN: llvm-mc -filetype=obj -triple=thumbv7a-windows-gnu %S/Inputs/far-arm-thumb-abs20.s -o %t.far.obj
// RUN: not lld-link -entry:_start -subsystem:console %t.obj %t.far.obj -out:%t.exe 2>&1 | FileCheck %s
.syntax unified
.globl _start
_start:
bne too_far20
// CHECK: relocation out of range