diff options
Diffstat (limited to 'stap.1.in')
| -rw-r--r-- | stap.1.in | 20 |
1 files changed, 16 insertions, 4 deletions
@@ -72,7 +72,7 @@ prints a list of supported options. .\" -t test mode .TP .B \-v -Verbose mode. Produces more informative output. +Verbose mode. Produce more informative output. .TP .B \-h Show help message. @@ -86,9 +86,12 @@ in order to examine the generated C code, or to reuse the compiled kernel object. .TP .B \-g -Guru mode. Enables parsing of unsafe expert-level constructs like +Guru mode. Enable parsing of unsafe expert-level constructs like embedded C. .TP +.B \-u +Unoptimized mode. Disable unused code elision during elaboration. +.TP .BI \-b Use relayfs-based bulk mode for kernel-to-user data transfer. .TP @@ -583,11 +586,11 @@ and all scripts (files named .IR *.stp ) found in a tapset directory. The directories listed with -.BR -I +.BR \-I are processed in sequence, each processed in "guru mode". For each directory, a number of subdirectories are also searched. These subdirectories are derived from the selected kernel version (the -.BR -R +.BR \-R option), in order to allow more kernel-version-specific scripts to override less specific ones. For example, for a kernel version @@ -617,6 +620,15 @@ appropriate kernel debugging information to be installed. In the associated probe handlers, target-side variables (whose names begin with "$") are found and have their run-time locations decoded. .PP +Next, all probes and functions are analyzed for optimization +opportunities, in order to remove variables, expressions, and +functions that have no useful value and no side-effect. Since this +process can hide latent code errors such as type mismatches or invalid +$target variables, it sometimes may be useful to disable the +optimizations with the +.BR \-u +option. +.PP Finally, all variable, function, parameter, array, and index types are inferred from context (literals and operators). Stopping the translator after pass 2 causes it to list all the probes, functions, |