llvm-toolchain/debian/patches/libcxx/libcxx-riscv64-cycletimer.diff
Aurelien Jarno fdacc67577 Add support for riscv64:
* Add support for riscv64:
  - Always link with -latomic on riscv64.
  - patches/clang-riscv64-multiarch.diff: add multiarch paths for riscv64.
  - patches/clang-riscv64-rv64gc.diff: default to lp64d ABI and rv64gc ISA.
  - patches/clang-riscv64-hf-abi.diff: backport riscv64 hard-float support
    from upstream.
  - patches/libcxx/libcxx-riscv64-cycletimer.diff: backport riscv64
    cycletimer support from upstream.
2019-08-02 12:46:43 +02:00

82 lines
3.1 KiB
Diff

commit 09e6304440c08fe72b6ac05f922ab9d8b7f1e387
Author: Roger Ferrer Ibanez <rofirrim@gmail.com>
Date: Wed Jul 24 05:33:46 2019 +0000
[RISCV] Implement benchmark::cycleclock::Now
This is a cherrypick of D64237 onto llvm/utils/benchmark and
libcxx/utils/google-benchmark.
Differential Revision: https://reviews.llvm.org/D65142
llvm-svn: 366868
--- a/libcxx/utils/google-benchmark/README.LLVM
+++ b/libcxx/utils/google-benchmark/README.LLVM
@@ -4,3 +4,9 @@ LLVM notes
This directory contains the Google Benchmark source code with some unnecessary
files removed. Note that this directory is under a different license than
libc++.
+
+Changes:
+* https://github.com/google/benchmark/commit/4abdfbb802d1b514703223f5f852ce4a507d32d2
+ is applied on top of
+ https://github.com/google/benchmark/commit/4528c76b718acc9b57956f63069c699ae21edcab
+ to add RISC-V timer support.
--- a/libcxx/utils/google-benchmark/src/cycleclock.h
+++ b/libcxx/utils/google-benchmark/src/cycleclock.h
@@ -164,6 +164,21 @@ inline BENCHMARK_ALWAYS_INLINE int64_t Now() {
uint64_t tsc;
asm("stck %0" : "=Q"(tsc) : : "cc");
return tsc;
+#elif defined(__riscv) // RISC-V
+ // Use RDCYCLE (and RDCYCLEH on riscv32)
+#if __riscv_xlen == 32
+ uint64_t cycles_low, cycles_hi0, cycles_hi1;
+ asm("rdcycleh %0" : "=r"(cycles_hi0));
+ asm("rdcycle %0" : "=r"(cycles_lo));
+ asm("rdcycleh %0" : "=r"(cycles_hi1));
+ // This matches the PowerPC overflow detection, above
+ cycles_lo &= -static_cast<int64_t>(cycles_hi0 == cycles_hi1);
+ return (cycles_hi1 << 32) | cycles_lo;
+#else
+ uint64_t cycles;
+ asm("rdcycle %0" : "=r"(cycles));
+ return cycles;
+#endif
#else
// The soft failover to a generic implementation is automatic only for ARM.
// For other platforms the developer is expected to make an attempt to create
--- a/utils/benchmark/README.LLVM
+++ b/utils/benchmark/README.LLVM
@@ -23,3 +23,5 @@ Changes:
is applied to disable exceptions in Microsoft STL when exceptions are disabled
* Disabled CMake get_git_version as it is meaningless for this in-tree build,
and hardcoded a null version
+* https://github.com/google/benchmark/commit/4abdfbb802d1b514703223f5f852ce4a507d32d2
+ is applied on top of v1.4.1 to add RISC-V timer support.
--- a/utils/benchmark/src/cycleclock.h
+++ b/utils/benchmark/src/cycleclock.h
@@ -164,6 +164,21 @@ inline BENCHMARK_ALWAYS_INLINE int64_t Now() {
uint64_t tsc;
asm("stck %0" : "=Q" (tsc) : : "cc");
return tsc;
+#elif defined(__riscv) // RISC-V
+ // Use RDCYCLE (and RDCYCLEH on riscv32)
+#if __riscv_xlen == 32
+ uint64_t cycles_low, cycles_hi0, cycles_hi1;
+ asm("rdcycleh %0" : "=r"(cycles_hi0));
+ asm("rdcycle %0" : "=r"(cycles_lo));
+ asm("rdcycleh %0" : "=r"(cycles_hi1));
+ // This matches the PowerPC overflow detection, above
+ cycles_lo &= -static_cast<int64_t>(cycles_hi0 == cycles_hi1);
+ return (cycles_hi1 << 32) | cycles_lo;
+#else
+ uint64_t cycles;
+ asm("rdcycle %0" : "=r"(cycles));
+ return cycles;
+#endif
#else
// The soft failover to a generic implementation is automatic only for ARM.
// For other platforms the developer is expected to make an attempt to create