[llvm] 974f973 - [dwarfdump][AMDGPU] Support EF_AMDGPU_MACH_NONE
Scott Linder via llvm-commits
llvm-commits at lists.llvm.org
Wed Apr 19 08:02:36 PDT 2023
Author: Scott Linder
Date: 2023-04-19T15:02:11Z
New Revision: 974f973d26a688f830fc7204a452b63f2f6cf868
URL: https://github.com/llvm/llvm-project/commit/974f973d26a688f830fc7204a452b63f2f6cf868
DIFF: https://github.com/llvm/llvm-project/commit/974f973d26a688f830fc7204a452b63f2f6cf868.diff
LOG: [dwarfdump][AMDGPU] Support EF_AMDGPU_MACH_NONE
A quirk of the AMDGPU backend is EF_AMDGPU_MACH_NONE, which is not
specific to the r600 or amdgcn architecture, but can be combined with
either.
AMDGPU ELF code objects with this mach value cannot be mapped back to a
Triple architecture, as it could be either r600 or amdgcn. For
llvm-dwarfdump this means the normal method of inspecting
ObjectFile::getArch to determine how to handle relocations is
insufficient.
This patch adds an extra check for ELF code objects which would
otherwise be categorized as UnknownArch, making it possible to use
llvm-dwarfdump with them. For completeness it also adds support for
known r600 machines.
This also adds specific tests for llvm-dwarfdump for amdgcn and r600,
both with known and unknown mach values.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D144301
Added:
llvm/test/tools/llvm-dwarfdump/AMDGPU/amdgpu-relocs.yaml
llvm/test/tools/llvm-dwarfdump/AMDGPU/lit.local.cfg
Modified:
llvm/lib/Object/RelocationResolver.cpp
Removed:
################################################################################
diff --git a/llvm/lib/Object/RelocationResolver.cpp b/llvm/lib/Object/RelocationResolver.cpp
index 5a0edaf457b2f..03ac592895284 100644
--- a/llvm/lib/Object/RelocationResolver.cpp
+++ b/llvm/lib/Object/RelocationResolver.cpp
@@ -252,6 +252,19 @@ static uint64_t resolveSparc64(uint64_t Type, uint64_t Offset, uint64_t S,
}
}
+/// Returns true if \c Obj is an AMDGPU code object based solely on the value
+/// of e_machine.
+///
+/// AMDGPU code objects with an e_machine of EF_AMDGPU_MACH_NONE do not
+/// identify their arch as either r600 or amdgcn, but we can still handle
+/// their relocations. When we identify an ELF object with an UnknownArch,
+/// we use isAMDGPU to check for this case.
+static bool isAMDGPU(const ObjectFile &Obj) {
+ if (const auto *ELFObj = dyn_cast<ELFObjectFileBase>(&Obj))
+ return ELFObj->getEMachine() == ELF::EM_AMDGPU;
+ return false;
+}
+
static bool supportsAmdgpu(uint64_t Type) {
switch (Type) {
case ELF::R_AMDGPU_ABS32:
@@ -789,6 +802,8 @@ getRelocationResolver(const ObjectFile &Obj) {
case Triple::riscv64:
return {supportsRISCV, resolveRISCV};
default:
+ if (isAMDGPU(Obj))
+ return {supportsAmdgpu, resolveAmdgpu};
return {nullptr, nullptr};
}
}
@@ -821,11 +836,15 @@ getRelocationResolver(const ObjectFile &Obj) {
return {supportsSparc32, resolveSparc32};
case Triple::hexagon:
return {supportsHexagon, resolveHexagon};
+ case Triple::r600:
+ return {supportsAmdgpu, resolveAmdgpu};
case Triple::riscv32:
return {supportsRISCV, resolveRISCV};
case Triple::csky:
return {supportsCSKY, resolveCSKY};
default:
+ if (isAMDGPU(Obj))
+ return {supportsAmdgpu, resolveAmdgpu};
return {nullptr, nullptr};
}
} else if (Obj.isMachO()) {
diff --git a/llvm/test/tools/llvm-dwarfdump/AMDGPU/amdgpu-relocs.yaml b/llvm/test/tools/llvm-dwarfdump/AMDGPU/amdgpu-relocs.yaml
new file mode 100644
index 0000000000000..669a4025ccf01
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/AMDGPU/amdgpu-relocs.yaml
@@ -0,0 +1,221 @@
+## Tests llvm-dwarfdump handling of AMDGPU relocations. We provide a .debug_info
+## section with multiple DW_AT_high_pc entries (that's one of the attributes for
+## which relocations are resolved by llvm-dwarfdump) and we add a relocation for
+## each of them. The first YAML document represents an amdgcn code object, and
+## the second an r600 code object.
+
+# RUN: yaml2obj --docnum=1 -DMACH= %s \
+# RUN: | llvm-dwarfdump - 2>&1 | FileCheck --check-prefixes=AMDGCN,UNKNOWN %s
+# RUN: yaml2obj --docnum=1 -DMACH=EF_AMDGPU_MACH_AMDGCN_GFX803 %s \
+# RUN: | llvm-dwarfdump - 2>&1 | FileCheck --check-prefixes=AMDGCN,KNOWN %s
+
+# RUN: yaml2obj --docnum=2 -DMACH= %s \
+# RUN: | llvm-dwarfdump - 2>&1 | FileCheck --check-prefixes=R600,UNKNOWN %s
+# RUN: yaml2obj --docnum=2 -DMACH=EF_AMDGPU_MACH_R600_R600 %s \
+# RUN: | llvm-dwarfdump - 2>&1 | FileCheck --check-prefixes=R600,KNOWN %s
+
+# UNKNOWN: -: Error in creating MCRegInfo
+# KNOWN-NOT: -: Error in creating MCRegInfo
+
+# AMDGCN: -: file format elf64-amdgpu
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ OSABI: ELFOSABI_AMDGPU_HSA
+ ABIVersion: 0x02
+ Type: ET_REL
+ Machine: EM_AMDGPU
+ Flags: [[[MACH]]]
+DWARF:
+ debug_abbrev:
+ - Table:
+ - Code: 1
+ Tag: DW_TAG_compile_unit
+ Children: DW_CHILDREN_no
+ Attributes:
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ debug_info:
+ - Version: 4
+ AddrSize: 8
+ Entries:
+ - AbbrCode: 1
+ Values:
+ - Value: 0x4242424242424242
+ - Value: 0x4242424242424242
+ - Value: 0x4242424242424242
+ - Value: 0x4242424242424242
+ - Value: 0x4242424242424242
+ - Value: 0x4242424242424242
+ - Value: 0x4242424242424242
+ - Value: 0x4242424242424242
+Sections:
+ - Name: .rela.debug_info
+ Type: SHT_RELA
+ Flags: [ SHF_INFO_LINK ]
+ AddressAlign: 0x0000000000000008
+ Info: .debug_info
+ Relocations:
+
+ # AMDGCN: DW_AT_high_pc (0x0000000000000001)
+ - Offset: 0x000000000000000C # 0xC + 8*0
+ Type: R_AMDGPU_ABS64
+ Symbol: v1
+ Addend: 0x0
+
+ # AMDGCN-NEXT: DW_AT_high_pc (0x0000000000000043)
+ - Offset: 0x0000000000000014 # 0xC + 8*1
+ Type: R_AMDGPU_ABS64
+ Symbol: v1
+ Addend: 0x42
+
+ # AMDGCN-NEXT: DW_AT_high_pc (0xffffffffffffffff)
+ - Offset: 0x000000000000001C # 0xC + 8*2
+ Type: R_AMDGPU_ABS64
+ Symbol: v0
+ Addend: 0xffffffffffffffff
+
+ # AMDGCN-NEXT: DW_AT_high_pc (0xffffffffffffffff)
+ - Offset: 0x0000000000000024 # 0xC + 8*3
+ Type: R_AMDGPU_ABS64
+ Symbol: vffffffffffffffff
+ Addend: 0x0
+
+ # AMDGCN: DW_AT_high_pc (0x0000000000000001)
+ - Offset: 0x000000000000002C # 0xC + 8*4
+ Type: R_AMDGPU_ABS32
+ Symbol: v1
+ Addend: 0x0
+
+ # AMDGCN-NEXT: DW_AT_high_pc (0x0000000000000043)
+ - Offset: 0x0000000000000034 # 0xC + 8*5
+ Type: R_AMDGPU_ABS32
+ Symbol: v1
+ Addend: 0x42
+
+ # AMDGCN-NEXT: DW_AT_high_pc (0xffffffffffffffff)
+ - Offset: 0x000000000000003C # 0xC + 8*6
+ Type: R_AMDGPU_ABS32
+ Symbol: v0
+ Addend: 0xffffffffffffffff
+
+ # AMDGCN-NEXT: DW_AT_high_pc (0xffffffffffffffff)
+ - Offset: 0x0000000000000044 # 0xC + 8*7
+ Type: R_AMDGPU_ABS32
+ Symbol: vffffffffffffffff
+ Addend: 0x0
+
+Symbols:
+ - Name: v0
+ Type: STT_SECTION
+ Section: .debug_info
+ Value: 0x0
+ - Name: v1
+ Type: STT_SECTION
+ Section: .debug_info
+ Value: 0x1
+ - Name: vffffffffffffffff
+ Type: STT_SECTION
+ Section: .debug_info
+ Value: 0xffffffffffffffff
+...
+
+# R600: -: file format elf32-amdgpu
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS32
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_AMDGPU
+ Flags: [[[MACH]]]
+DWARF:
+ debug_abbrev:
+ - Table:
+ - Code: 0x00000001
+ Tag: DW_TAG_compile_unit
+ Children: DW_CHILDREN_no
+ Attributes:
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ - Attribute: DW_AT_high_pc
+ Form: DW_FORM_addr
+ debug_info:
+ - Version: 4
+ AddrSize: 4
+ Entries:
+ - AbbrCode: 1
+ Values:
+ - Value: 0x42424242
+ - Value: 0x42424242
+ - Value: 0x42424242
+ - Value: 0x42424242
+Sections:
+ - Name: .rela.debug_info
+ Type: SHT_RELA
+ Flags: [ SHF_INFO_LINK ]
+ AddressAlign: 0x0000000000000001
+ Info: .debug_info
+ Relocations:
+
+ ## FIXME: Is R_AMDGPU_ABS64 meaningful here?
+
+ # R600: DW_AT_high_pc (0x00000001)
+ - Offset: 0x0000000C # 0xC + 4*0
+ Type: R_AMDGPU_ABS32
+ Symbol: v1
+ Addend: 0x0
+
+ # R600-NEXT: DW_AT_high_pc (0x00000043)
+ - Offset: 0x00000010 # 0xC + 4*1
+ Type: R_AMDGPU_ABS32
+ Symbol: v1
+ Addend: 0x42
+
+ ## FIXME: Why is this field printed as sign-extended 64-bit in a 32-bit executable?
+ # R600-NEXT: DW_AT_high_pc (0xffffffffffffffff)
+ - Offset: 0x00000014 # 0xC + 4*2
+ Type: R_AMDGPU_ABS32
+ Symbol: v0
+ Addend: 0xffffffff
+
+ # R600-NEXT: DW_AT_high_pc (0xffffffff)
+ - Offset: 0x00000018 # 0xC + 4*3
+ Type: R_AMDGPU_ABS32
+ Symbol: vffffffff
+ Addend: 0x0
+
+Symbols:
+ - Name: v0
+ Type: STT_SECTION
+ Section: .debug_info
+ Value: 0x0
+ - Name: v1
+ Type: STT_SECTION
+ Section: .debug_info
+ Value: 0x1
+ - Name: vffffffff
+ Type: STT_SECTION
+ Section: .debug_info
+ Value: 0xffffffff
+...
diff --git a/llvm/test/tools/llvm-dwarfdump/AMDGPU/lit.local.cfg b/llvm/test/tools/llvm-dwarfdump/AMDGPU/lit.local.cfg
new file mode 100644
index 0000000000000..2a665f06be72e
--- /dev/null
+++ b/llvm/test/tools/llvm-dwarfdump/AMDGPU/lit.local.cfg
@@ -0,0 +1,2 @@
+if not 'AMDGPU' in config.root.targets:
+ config.unsupported = True
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