How to understand output of "llvm-profdata show"

Question

I got some profiling data (code.profdata) for my process using clang-3.8 build/link option:

 -fprofile-instr-generate

I generated the output using:

llvm-profdata show -all-functions -counts -ic-targets -output=llvm_prof.log  code.profdata

1. I am trying to make sense of the but I am not sure how to interpret it, what each field in output means.
2. Is there any llvm tool that can process this data like kcachegrind.

Thanks!

Data:

Counters:
  fn1:
    Hash: 0x878e8bfe5d1b6a20
    Counters: 8
    Function count: 4464
    Indirect Call Site Count: 0
    Block counts: [4464, 0, 294838272, 0, 4464, 0, 4464]
    Indirect Target Results:
  file1.c:fn2:
    Hash: 0x36804e8dae059d63
    Counters: 6
    Function count: 24576
    Indirect Call Site Count: 0
    Block counts: [24576, 24576, 0, 24576, 24576]
    Indirect Target Results:
  file2.c:fn3:
    Hash: 0x000000000000028a
    Counters: 3
    Function count: 0
    Indirect Call Site Count: 0
    Block counts: [0, 0]
    Indirect Target Results:
  file3.c:fn4:
    Hash: 0x0000000000000000
    Counters: 1
    Function count: 0
    Indirect Call Site Count: 0
    Block counts: []
    Indirect Target Results:

Answer 1

I was missing one step.
LLVM toolchain provides another tool - llvm-cov Output of llvm-profdata merge needs to be passed to llvm-cov to link the function counter data to source code, like so:

llvm-cov show test.bin -instr-profile=merge.out

It will generate output:

       |    1|#include <stdio.h>
       |    2|#include <stdlib.h>
  1.11k|    3|#define CTR 10
       |    4|
       |    5|int
       |    6|main()
      1|    7|{
      1|    8|    int i, j, k;
     11|    9|    for(i=0; i < CTR; ++i) {
     10|   10|        printf("3: %d", i);
     10|   11|    }
    101|   12|    for(i=0; i < CTR*10; ++i) {
    100|   13|        printf("3: %d", i);
    100|   14|    }
  1.00k|   15|    for(i=0; i < CTR*100; ++i) {
  1.00k|   16|        printf("3: %d", i);
  1.00k|   17|    }
      1|   18|    //  exit(0);
      1|   19|    return 0;

      1|   20|}

For completenes, entire flow:

#1 generate instrumented binary

clang-9  -g profile_coverage.c  -fprofile-instr-generate -fcoverage-mapping -o profile_coverage

#2 run binary and get prof data.

export LLVM_PROFILE_FILE=./llvm_%p.prof 
./profile_coverage > /dev/null
// when program exits, it produces output file llvm_9150.prof

#3 merge

$  llvm-profdata-9 merge -output=merge.out -instr llvm_9150.prof
// outputs merge.out

#4 coverage with instrumented source

$  llvm-cov-9 show profile_coverage  -instr-profile=merge.out

Wrote a blog post covering the whole flow: link