xen/arch/x86/xen.lds.S | 6 +++++ xen/common/coverage/llvm.c | 54 +++++++++++++++++++++++++++++++++----- xen/include/xen/xen.lds.h | 13 +++++++++ 3 files changed, 67 insertions(+), 6 deletions(-)
This change enables compatibility for measuring code coverage
with Clang versions 11 through 20 by supporting their respective raw
profile formats.
1- Added support for LLVM raw profile versions 5, 6, 7, 8, 9, and 10.
2- Initialized llvm_profile_header for all versions based on llvm source
code in compiler-rt/include/profile/InstrProfData.inc for each version.
3- We tested this patch for all Clang versions from 11 through 20
on x86 platform.
4- Fixed linking warnings related to LLVM profile sections in x86.
Signed-off-by: Saman Dehghan <samaan.dehghan@gmail.com>
Release-Acked-By: Oleksii Kurochko <oleksii.kurochko@gmail.com>
Tested-by: Wentao Zhang <wentaoz5@illinois.edu>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
---
Changes from v3 to v4:
1- Use LLVM_PROFILE_VERSION in preprocessor conditionals
instead of __clang_major__.
2- Use DIV_ROUND_UP helper.
3- Remove unnecessary zero initialization inside struct.
4- Remove fallback macro definitions in linker script.
Changes from v2 to v3:
1- Additionally support raw profile version 5, 6, 7 in clang 11, 12, 13.
2- Fix coverage related linking warnings in x86.
3- Revert unnecessary type changes, casting, etc.
---
xen/arch/x86/xen.lds.S | 6 +++++
xen/common/coverage/llvm.c | 54 +++++++++++++++++++++++++++++++++-----
xen/include/xen/xen.lds.h | 13 +++++++++
3 files changed, 67 insertions(+), 6 deletions(-)
diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S
index 966e514f20..5d02f83a40 100644
--- a/xen/arch/x86/xen.lds.S
+++ b/xen/arch/x86/xen.lds.S
@@ -186,6 +186,8 @@ SECTIONS
} PHDR(note) PHDR(text)
#endif
+ LLVM_COV_RO_DATA
+
_erodata = .;
. = ALIGN(SECTION_ALIGN);
@@ -323,6 +325,8 @@ SECTIONS
*(.data .data.*)
} PHDR(text)
+ LLVM_COV_RW_DATA
+
DECL_SECTION(.bss) {
__bss_start = .;
*(.bss.page_aligned*)
@@ -357,6 +361,8 @@ SECTIONS
DWARF2_DEBUG_SECTIONS
+ LLVM_COV_DEBUG
+
#ifdef CONFIG_HYPERV_GUEST
hv_hcall_page = ABSOLUTE(HV_HCALL_PAGE - XEN_VIRT_START + __XEN_VIRT_START);
#endif
diff --git a/xen/common/coverage/llvm.c b/xen/common/coverage/llvm.c
index 517b2aa8c2..532889c857 100644
--- a/xen/common/coverage/llvm.c
+++ b/xen/common/coverage/llvm.c
@@ -44,27 +44,65 @@
((uint64_t)'f' << 16) | ((uint64_t)'R' << 8) | ((uint64_t)129)
#endif
-#define LLVM_PROFILE_VERSION 4
+#if __clang_major__ >= 19 && __clang_major__ <= 20
+#define LLVM_PROFILE_VERSION 10
+#define LLVM_PROFILE_NUM_KINDS 3
+#elif __clang_major__ == 18
+#define LLVM_PROFILE_VERSION 9
#define LLVM_PROFILE_NUM_KINDS 2
+#elif __clang_major__ >= 14
+#define LLVM_PROFILE_VERSION 8
+#define LLVM_PROFILE_NUM_KINDS 2
+#elif __clang_major__ == 13
+#define LLVM_PROFILE_VERSION 7
+#define LLVM_PROFILE_NUM_KINDS 2
+#elif __clang_major__ >= 11
+#define LLVM_PROFILE_VERSION 5
+#define LLVM_PROFILE_NUM_KINDS 2
+#else
+#error "LLVM coverage selected but an unsupported clang version is used"
+#endif
struct llvm_profile_data {
uint64_t name_ref;
uint64_t function_hash;
- void *counter;
+ void *relative_counter;
+#if LLVM_PROFILE_VERSION >= 9
+ void *relative_bitmap;
+#endif
void *function;
void *values;
uint32_t nr_counters;
uint16_t nr_value_sites[LLVM_PROFILE_NUM_KINDS];
+#if LLVM_PROFILE_VERSION >= 9
+ uint32_t numbitmap_bytes;
+#endif
};
struct llvm_profile_header {
uint64_t magic;
uint64_t version;
- uint64_t data_size;
- uint64_t counters_size;
+#if LLVM_PROFILE_VERSION >= 7
+ uint64_t binary_ids_size;
+#endif
+ uint64_t num_data;
+ uint64_t padding_bytes_before_counters;
+ uint64_t num_counters;
+ uint64_t padding_bytes_after_counters;
+#if LLVM_PROFILE_VERSION >= 9
+ uint64_t num_bitmap_bytes;
+ uint64_t padding_bytes_after_bitmap_bytes;
+#endif
uint64_t names_size;
uint64_t counters_delta;
+#if LLVM_PROFILE_VERSION >= 9
+ uint64_t bitmap_delta;
+#endif
uint64_t names_delta;
+#if LLVM_PROFILE_VERSION == 10
+ uint64_t num_vtables;
+ uint64_t vnames_size;
+#endif
uint64_t value_kind_last;
};
@@ -107,10 +145,14 @@ static int cf_check dump(
struct llvm_profile_header header = {
.magic = LLVM_PROFILE_MAGIC,
.version = LLVM_PROFILE_VERSION,
- .data_size = (END_DATA - START_DATA) / sizeof(struct llvm_profile_data),
- .counters_size = (END_COUNTERS - START_COUNTERS) / sizeof(uint64_t),
+ .num_data = DIV_ROUND_UP(END_DATA - START_DATA, sizeof(struct llvm_profile_data)),
+ .num_counters = DIV_ROUND_UP(END_COUNTERS - START_COUNTERS, sizeof(uint64_t)),
.names_size = END_NAMES - START_NAMES,
+#if LLVM_PROFILE_VERSION >= 8
+ .counters_delta = START_COUNTERS - START_DATA,
+#else
.counters_delta = (uintptr_t)START_COUNTERS,
+#endif
.names_delta = (uintptr_t)START_NAMES,
.value_kind_last = LLVM_PROFILE_NUM_KINDS - 1,
};
diff --git a/xen/include/xen/xen.lds.h b/xen/include/xen/xen.lds.h
index b126dfe887..d80c895959 100644
--- a/xen/include/xen/xen.lds.h
+++ b/xen/include/xen/xen.lds.h
@@ -81,6 +81,19 @@
.stab.index 0 : { *(.stab.index) } \
.stab.indexstr 0 : { *(.stab.indexstr) }
+/* Clang coverage sections. */
+#define LLVM_COV_RW_DATA \
+ DECL_SECTION(__llvm_prf_cnts) { *(__llvm_prf_cnts) } \
+ DECL_SECTION(__llvm_prf_data) { *(__llvm_prf_data) } \
+ DECL_SECTION(__llvm_prf_bits) { *(__llvm_prf_bits) }
+
+#define LLVM_COV_RO_DATA \
+ DECL_SECTION(__llvm_prf_names) { *(__llvm_prf_names) }
+
+#define LLVM_COV_DEBUG \
+ DECL_DEBUG(__llvm_covfun, 8) \
+ DECL_DEBUG(__llvm_covmap, 8)
+
/*
* ELF sections.
*
--
2.49.0On 27/10/2025 9:30 pm, Saman Dehghan wrote: > This change enables compatibility for measuring code coverage > with Clang versions 11 through 20 by supporting their respective raw > profile formats. > > 1- Added support for LLVM raw profile versions 5, 6, 7, 8, 9, and 10. > 2- Initialized llvm_profile_header for all versions based on llvm source > code in compiler-rt/include/profile/InstrProfData.inc for each version. > 3- We tested this patch for all Clang versions from 11 through 20 > on x86 platform. > 4- Fixed linking warnings related to LLVM profile sections in x86. > > > Signed-off-by: Saman Dehghan <samaan.dehghan@gmail.com> > Release-Acked-By: Oleksii Kurochko <oleksii.kurochko@gmail.com> > Tested-by: Wentao Zhang <wentaoz5@illinois.edu> > Acked-by: Andrew Cooper <andrew.cooper3@citrix.com> > --- > Changes from v3 to v4: > 1- Use LLVM_PROFILE_VERSION in preprocessor conditionals > instead of __clang_major__. > 2- Use DIV_ROUND_UP helper. > 3- Remove unnecessary zero initialization inside struct. > 4- Remove fallback macro definitions in linker script. > Changes from v2 to v3: > 1- Additionally support raw profile version 5, 6, 7 in clang 11, 12, 13. > 2- Fix coverage related linking warnings in x86. > 3- Revert unnecessary type changes, casting, etc. > --- Excellent. Thankyou. This all looks in order. I've committed it. ~Andrew
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