Document reference commands and selective failures in the man page

doc/hyperfine.1

@@ -3,7 +3,8 @@
 hyperfine \- command\-line benchmarking tool
 .SH SYNOPSIS
 .B hyperfine
-.RB [ \-ihVN ]
+.RB [ \-hVN ]
+.RB [ \-\-ignore\-failure[=MODE] ]
 .RB [ \-\-warmup
 .IR NUM ]
 .RB [ \-\-min\-runs
@@ -14,6 +15,10 @@ hyperfine \- command\-line benchmarking tool
 .IR NUM ]
 .RB [ \-\-setup
 .IR CMD ]
+.RB [ \-\-reference
+.IR CMD ]
+.RB [ \-\-reference\-name
+.IR NAME ]
 .RB [ \-\-prepare
 .IR CMD ]
 .RB [ \-\-conclude
@@ -109,6 +114,16 @@ for compiling your software or with the provided parameters, or to do any
 other work that should happen once before a series of benchmark runs,
 not every time as would happen with the \fB\-\-prepare\fR option.
 .HP
+\fB\-\-reference\fR \fICMD\fP
+.IP
+Benchmark \fICMD\fP as the reference for the relative comparison of results.
+If this option is not specified, the fastest command is used as the reference.
+.HP
+\fB\-\-reference\-name\fR \fINAME\fP
+.IP
+Give a meaningful \fINAME\fP to the reference command.
+Requires \fB\-\-reference\fR.
+.HP
 \fB\-p\fR, \fB\-\-prepare\fR \fICMD...\fP
 .IP
 Execute \fICMD\fP before each timing run. This is useful for clearing disk caches,
@@ -141,7 +156,7 @@ string '{\fIVAR\fP}' in each command by the current parameter value.
 .RS
 Example:
 .RS
-\fBhyperfine\fR \fB\-\-prepare\fR 'make clean' \fB\-P\fR threads 1 8 'make \-j {threads}'
+\fBhyperfine\fR \fB\-P\fR threads 1 8 'make \-j {threads}'
 .RE
 .RE
 .IP
@@ -207,9 +222,13 @@ things like "sleep 0.1; sleep 0.2" are not possible without a shell.
 .IP
 An alias for '\-\-shell=none'.
 .HP
-\fB\-i\fR, \fB\-\-ignore\-failure\fR
+\fB\-i\fR, \fB\-\-ignore\-failure\fR[=\fIMODE\fP]
 .IP
-Ignore non\-zero exit codes of the benchmarked programs.
+Ignore failures of the benchmarked programs. Without a value or with
+\fBall\-non\-zero\fR, all non\-zero exit codes are ignored.
+Alternatively, provide a comma\-separated list of exit codes to ignore,
+for example \fB\-\-ignore\-failure=1,2\fR.
+An explicit value must be attached to the option with an equals sign.
 .HP
 \fB\-\-style\fR \fITYPE\fP
 .IP

src/cli.rs

@@ -161,7 +161,7 @@ fn build_command() -> Command {
                 .help(
                     "Perform benchmark runs for each value in the range MIN..MAX. Replaces the \
                      string '{VAR}' in each command by the current parameter value.\n\n  \
-                     Example:  hyperfine --prepare 'make clean' -P threads 1 8 'make -j {threads}'\n\n\
+                     Example:  hyperfine -P threads 1 8 'make -j {threads}'\n\n\
                      This performs benchmarks for 'make -j 1', 'make -j 2', …, 'make -j 8'.\n\n\
                      To have the value increase following different patterns, use shell arithmetics.\n\n  \
                      Example: hyperfine -P size 0 3 'sleep $((2**{size}))'\n\n\