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Differential D56758

[WebAssembly] Store section alignment as a power of 2
ClosedPublic

Authored by sbc100 on Jan 15 2019, 4:27 PM.

Details

Reviewers
dschuff
Commits
rG56c587adfd29: [WebAssembly] Store section alignment as a power of 2
rL351285: [WebAssembly] Store section alignment as a power of 2
Summary

This change bumps for version number of the wasm object file
metadata.

See https://github.com/WebAssembly/tool-conventions/pull/92

Diff Detail

Event Timeline

sbc100 created this revision.Jan 15 2019, 4:27 PM
Herald added subscribers: llvm-commits, sunfish, aheejin and 2 others. · View Herald TranscriptJan 15 2019, 4:27 PM
Harbormaster completed remote builds in B26886: Diff 181924.Jan 15 2019, 4:27 PM
sbc100 added a reviewer: dschuff.Jan 15 2019, 4:27 PM
sbc100 updated this revision to Diff 181934.Jan 15 2019, 4:48 PM
  • update tests
Herald added a subscriber: rupprecht. · View Herald TranscriptJan 15 2019, 4:48 PM
Harbormaster completed remote builds in B26887: Diff 181934.Jan 15 2019, 4:49 PM
dschuff accepted this revision.Jan 15 2019, 4:52 PM

This code LGTM modulo whatever version number we settle on in the tool-conventions issue.

This revision is now accepted and ready to land.Jan 15 2019, 4:52 PM
Closed by commit rL351285: [WebAssembly] Store section alignment as a power of 2 (authored by sbc). · Explain WhyJan 15 2019, 5:38 PM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
include/
llvm/
BinaryFormat/
2 lines
lib/
MC/
2 lines
test/
MC/
WebAssembly/
2 lines

Diff 181924

include/llvm/BinaryFormat/Wasm.h

Show All 20 Lines
namespace llvm { namespace llvm {
namespace wasm { namespace wasm {
// Object file magic string. // Object file magic string.
const char WasmMagic[] = {'\0', 'a', 's', 'm'}; const char WasmMagic[] = {'\0', 'a', 's', 'm'};
// Wasm binary format version // Wasm binary format version
const uint32_t WasmVersion = 0x1; const uint32_t WasmVersion = 0x1;
// Wasm linking metadata version // Wasm linking metadata version
const uint32_t WasmMetadataVersion = 0x1; const uint32_t WasmMetadataVersion = 0x2;
// Wasm uses a 64k page size // Wasm uses a 64k page size
const uint32_t WasmPageSize = 65536; const uint32_t WasmPageSize = 65536;
struct WasmObjectHeader { struct WasmObjectHeader {
StringRef Magic; StringRef Magic;
uint32_t Version; uint32_t Version;
}; };
▲ Show 20 Lines • Show All 305 Lines • Show Last 20 Lines

lib/MC/WasmObjectWriter.cpp

Show First 20 Lines • Show All 1,250 Lines • ▼ Show 20 Lines if (Section.isWasmData()) {
uint32_t SegmentIndex = DataSegments.size(); uint32_t SegmentIndex = DataSegments.size();
DataSize = alignTo(DataSize, Section.getAlignment()); DataSize = alignTo(DataSize, Section.getAlignment());
DataSegments.emplace_back(); DataSegments.emplace_back();
WasmDataSegment &Segment = DataSegments.back(); WasmDataSegment &Segment = DataSegments.back();
Segment.Name = SectionName; Segment.Name = SectionName;
Segment.Offset = DataSize; Segment.Offset = DataSize;
Segment.Section = &Section; Segment.Section = &Section;
addData(Segment.Data, Section); addData(Segment.Data, Section);
Segment.Alignment = Section.getAlignment(); Segment.Alignment = Log2_32(Section.getAlignment());
Segment.Flags = 0; Segment.Flags = 0;
DataSize += Segment.Data.size(); DataSize += Segment.Data.size();
Section.setSegmentIndex(SegmentIndex); Section.setSegmentIndex(SegmentIndex);
if (const MCSymbolWasm *C = Section.getGroup()) { if (const MCSymbolWasm *C = Section.getGroup()) {
Comdats[C->getName()].emplace_back( Comdats[C->getName()].emplace_back(
WasmComdatEntry{wasm::WASM_COMDAT_DATA, SegmentIndex}); WasmComdatEntry{wasm::WASM_COMDAT_DATA, SegmentIndex});
} }
▲ Show 20 Lines • Show All 320 Lines • Show Last 20 Lines

test/MC/WebAssembly/array-fill.ll

Show All 16 Lines
; CHECK-NEXT: Kind: DATA ; CHECK-NEXT: Kind: DATA
; CHECK-NEXT: Name: gBd ; CHECK-NEXT: Name: gBd
; CHECK-NEXT: Flags: [ VISIBILITY_HIDDEN ] ; CHECK-NEXT: Flags: [ VISIBILITY_HIDDEN ]
; CHECK-NEXT: Segment: 0 ; CHECK-NEXT: Segment: 0
; CHECK-NEXT: Size: 2 ; CHECK-NEXT: Size: 2
; CHECK-NEXT: SegmentInfo: ; CHECK-NEXT: SegmentInfo:
; CHECK-NEXT: - Index: 0 ; CHECK-NEXT: - Index: 0
; CHECK-NEXT: Name: .data ; CHECK-NEXT: Name: .data
; CHECK-NEXT: Alignment: 1 ; CHECK-NEXT: Alignment: 0
; CHECK-NEXT: Flags: [ ] ; CHECK-NEXT: Flags: [ ]
; CHECK-NEXT: ... ; CHECK-NEXT: ...