Turning on Heat Colors for CFG by default

[knaumov]

Summary

This option seems to be very useful, so let's turn it on by default.
Concerning the test, it was not constructed to do the tests locally, so I have rewritten it a bit without changing its essence.

[davidxl]

lgtm.

[knaumov]

Closing due to commit: https://github.com/llvm/llvm-project/commit/055f58fcfc618cdad0a8cb66fbd4657cdc0d05e9

llvm/lib/Analysis/CFGPrinter.cpp

static cl::opt<std::string> CFGDotFilenamePrefix(
     cl::desc("The prefix used for the CFG dot file names."));
 
 static cl::opt<bool> HideUnreachablePaths("cfg-hide-unreachable-paths",
                                           cl::init(false));
 
 static cl::opt<bool> HideDeoptimizePaths("cfg-hide-deoptimize-paths",
                                          cl::init(false));
 
-static cl::opt<bool> ShowHeatColors("cfg-heat-colors", cl::init(false),
+static cl::opt<bool> ShowHeatColors("cfg-heat-colors", cl::init(true),
                                     cl::Hidden,
                                     cl::desc("Show heat colors in CFG"));
 
 static cl::opt<bool> UseRawEdgeWeight("cfg-raw-weights", cl::init(false),
                                       cl::Hidden,
                                       cl::desc("Use raw weights for labels. "
                                                "Use percentages as default."));
 

llvm/test/Other/cfg_deopt_unreach.ll

 ; RUN: rm -rf %t
 ; RUN: mkdir -p %t
 ; RUN: opt < %s -analyze -dot-cfg -cfg-hide-unreachable-paths -cfg-dot-filename-prefix=%t/unreach 2>/dev/null
 ; RUN: FileCheck %s -input-file=%t/unreach.callee.dot -check-prefix=UNREACH
 ; RUN: opt < %s -analyze -dot-cfg -cfg-hide-deoptimize-paths -cfg-dot-filename-prefix=%t/deopt 2>/dev/null
 ; RUN: FileCheck %s -input-file=%t/deopt.callee.dot -check-prefix=DEOPT
 ; RUN: opt < %s -analyze -dot-cfg -cfg-dot-filename-prefix=%t/no-flags 2>/dev/null
 ; RUN: FileCheck %s -input-file=%t/no-flags.callee.dot -check-prefix=NO-FLAGS
 ; RUN: opt < %s -analyze -dot-cfg -cfg-hide-unreachable-paths -cfg-hide-deoptimize-paths -cfg-dot-filename-prefix=%t/both-flags 2>/dev/null
 ; RUN: FileCheck %s -input-file=%t/both-flags.callee.dot -check-prefix=BOTH-FLAGS
 
 declare i8 @llvm.experimental.deoptimize.i8(...)
 
 define i8 @callee(i1* %c) alwaysinline {
-; NO-FLAGS: [shape=record,label="{%0:\l  %c0 = load volatile i1, i1* %c\l  br i1 %c0, label %lleft, label %lright\l|{<s0>T|<s1>F}}"];
-; DEOPT: [shape=record,label="{%0:\l  %c0 = load volatile i1, i1* %c\l  br i1 %c0, label %lleft, label %lright\l|{<s0>T|<s1>F}}"];
-; UNREACH: [shape=record,label="{%0:\l  %c0 = load volatile i1, i1* %c\l  br i1 %c0, label %lleft, label %lright\l|{<s0>T|<s1>F}}"];
-; BOTH-FLAGS-NOT: [shape=record,label="{%0:\l  %c0 = load volatile i1, i1* %c\l  br i1 %c0, label %lleft, label %lright\l|{<s0>T|<s1>F}}"];
   %c0 = load volatile i1, i1* %c
   br i1 %c0, label %lleft, label %lright
-; NO-FLAGS: [shape=record,label="{lleft:                                            \l  %v0 = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ \"deopt\"(i32 1)\l... ]\l  ret i8 %v0\l}"];
-; DEOPT-NOT: [shape=record,label="{lleft:                                            \l  %v0 = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ \"deopt\"(i32 1)\l... ]\l  ret i8 %v0\l}"];
-; UNREACH: [shape=record,label="{lleft:                                            \l  %v0 = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ \"deopt\"(i32 1)\l... ]\l  ret i8 %v0\l}"];
-; BOTH-FLAGS-NOT: [shape=record,label="{lleft:                                            \l  %v0 = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ \"deopt\"(i32 1)\l... ]\l  ret i8 %v0\l}"];
+; NO-FLAGS: label="{lleft:                                            \l  %v0 = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ \"deopt\"(i32 1)\l... ]\l  ret i8 %v0\l}"
+; DEOPT-NOT: label="{lleft:                                            \l  %v0 = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ \"deopt\"(i32 1)\l... ]\l  ret i8 %v0\l}"
+; UNREACH: label="{lleft:                                            \l  %v0 = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ \"deopt\"(i32 1)\l... ]\l  ret i8 %v0\l}"
+; BOTH-FLAGS-NOT: label="{lleft:                                            \l  %v0 = call i8 (...) @llvm.experimental.deoptimize.i8(i32 1) [ \"deopt\"(i32 1)\l... ]\l  ret i8 %v0\l}"
 lleft:
   %v0 = call i8(...) @llvm.experimental.deoptimize.i8(i32 1) [ "deopt"(i32 1) ]
   ret i8 %v0
 
-; NO-FLAGS: [shape=record,label="{lright:                                           \l  unreachable\l}"];
-; DEOPT: [shape=record,label="{lright:                                           \l  unreachable\l}"];
-; UNREACH-NOT: [shape=record,label="{lright:                                           \l  unreachable\l}"];
-; BOTH-FLAGS-NOT: [shape=record,label="{lright:                                           \l  unreachable\l}"];
+; NO-FLAGS: label="{lright:                                           \l  unreachable\l}"
+; DEOPT: label="{lright:                                           \l  unreachable\l}"
+; UNREACH-NOT: label="{lright:                                           \l  unreachable\l}"
+; BOTH-FLAGS-NOT: label="{lright:                                           \l  unreachable\l}"
 lright:
   unreachable
 }