[PGO] Value profile support for value ranges

This patch adds profile run time support to profile a range of values.
This interface will be used in profiling the size of memory intrinsic calls.

Differential Revision: http://reviews.llvm.org/D28964

llvm-svn: 297895

2 files changed, 45 insertions, 1 deletions

diff --git a/compiler-rt/lib/profile/InstrProfData.inc b/compiler-rt/lib/profile/InstrProfData.inc
index f7c22d10763..6ef1625d81c 100644
--- a/compiler-rt/lib/profile/InstrProfData.inc
+++ b/compiler-rt/lib/profile/InstrProfData.inc
@@ -153,7 +153,17 @@ INSTR_PROF_RAW_HEADER(uint64_t, ValueKindLast, IPVK_Last)
 VALUE_PROF_FUNC_PARAM(uint64_t, TargetValue, Type::getInt64Ty(Ctx)) \
                       INSTR_PROF_COMMA
 VALUE_PROF_FUNC_PARAM(void *, Data, Type::getInt8PtrTy(Ctx)) INSTR_PROF_COMMA
+#ifndef VALUE_RANGE_PROF
 VALUE_PROF_FUNC_PARAM(uint32_t, CounterIndex, Type::getInt32Ty(Ctx))
+#else /* VALUE_RANGE_PROF */
+VALUE_PROF_FUNC_PARAM(uint32_t, CounterIndex, Type::getInt32Ty(Ctx)) \
+                      INSTR_PROF_COMMA
+VALUE_PROF_FUNC_PARAM(uint64_t, PreciseRangeStart, Type::getInt64Ty(Ctx)) \
+                      INSTR_PROF_COMMA
+VALUE_PROF_FUNC_PARAM(uint64_t, PreciseRangeLast, Type::getInt64Ty(Ctx)) \
+                      INSTR_PROF_COMMA
+VALUE_PROF_FUNC_PARAM(uint64_t, LargeValue, Type::getInt64Ty(Ctx))
+#endif /*VALUE_RANGE_PROF */
 #undef VALUE_PROF_FUNC_PARAM
 #undef INSTR_PROF_COMMA
 /* VALUE_PROF_FUNC_PARAM end */
@@ -174,13 +184,15 @@ VALUE_PROF_FUNC_PARAM(uint32_t, CounterIndex, Type::getInt32Ty(Ctx))
  * name hash and the function address.
  */
 VALUE_PROF_KIND(IPVK_IndirectCallTarget, 0)
+/* For memory intrinsic functions size profiling. */
+VALUE_PROF_KIND(IPVK_MemOPSize, 1)
 /* These two kinds must be the last to be
  * declared. This is to make sure the string
  * array created with the template can be
  * indexed with the kind value.
  */
 VALUE_PROF_KIND(IPVK_First, IPVK_IndirectCallTarget)
-VALUE_PROF_KIND(IPVK_Last, IPVK_IndirectCallTarget)
+VALUE_PROF_KIND(IPVK_Last, IPVK_MemOPSize)
 
 #undef VALUE_PROF_KIND
 /* VALUE_PROF_KIND end */
@@ -649,6 +661,9 @@ serializeValueProfDataFrom(ValueProfRecordClosure *Closure,
 #define INSTR_PROF_VALUE_PROF_FUNC __llvm_profile_instrument_target
 #define INSTR_PROF_VALUE_PROF_FUNC_STR \
         INSTR_PROF_QUOTE(INSTR_PROF_VALUE_PROF_FUNC)
+#define INSTR_PROF_VALUE_RANGE_PROF_FUNC __llvm_profile_instrument_range
+#define INSTR_PROF_VALUE_RANGE_PROF_FUNC_STR \
+        INSTR_PROF_QUOTE(INSTR_PROF_VALUE_RANGE_PROF_FUNC)
 
 /* InstrProfile per-function control data alignment.  */
 #define INSTR_PROF_DATA_ALIGNMENT 8
diff --git a/compiler-rt/lib/profile/InstrProfilingValue.c b/compiler-rt/lib/profile/InstrProfilingValue.c
index 6648f892358..44263da8009 100644
--- a/compiler-rt/lib/profile/InstrProfilingValue.c
+++ b/compiler-rt/lib/profile/InstrProfilingValue.c
@@ -220,6 +220,35 @@ __llvm_profile_instrument_target(uint64_t TargetValue, void *Data,
 }
 
 /*
+ * The target values are partitioned into multiple regions/ranges. There is one
+ * contiguous region which is precise -- every value in the range is tracked
+ * individually. A value outside the precise region will be collapsed into one
+ * value depending on the region it falls in.
+ *
+ * There are three regions:
+ * 1. (-inf, PreciseRangeStart) and (PreciseRangeLast, LargeRangeValue) belong
+ * to one region -- all values here should be mapped to one value of
+ * "PreciseRangeLast + 1".
+ * 2. [PreciseRangeStart, PreciseRangeLast]
+ * 3. Large values: [LargeValue, +inf) maps to one value of LargeValue.
+ *
+ * The range for large values is optional. The default value of INT64_MIN
+ * indicates it is not specified.
+ */
+COMPILER_RT_VISIBILITY void __llvm_profile_instrument_range(
+    uint64_t TargetValue, void *Data, uint32_t CounterIndex,
+    int64_t PreciseRangeStart, int64_t PreciseRangeLast, int64_t LargeValue) {
+
+  if (LargeValue != INT64_MIN && (int64_t)TargetValue >= LargeValue)
+    TargetValue = LargeValue;
+  else if ((int64_t)TargetValue < PreciseRangeStart ||
+           (int64_t)TargetValue > PreciseRangeLast)
+    TargetValue = PreciseRangeLast + 1;
+
+  __llvm_profile_instrument_target(TargetValue, Data, CounterIndex);
+}
+
+/*
  * A wrapper struct that represents value profile runtime data.
  * Like InstrProfRecord class which is used by profiling host tools,
  * ValueProfRuntimeRecord also implements the abstract intefaces defined in