[ARM] Read memory as unsigned integer

[deliverable/binutils-gdb.git] / gdb / doc / agentexpr.texi

diff --git a/gdb/doc/agentexpr.texi b/gdb/doc/agentexpr.texi
index 21042351ebb948b8999727be8fc7d93a4e47abc0..ade76380ec59c49956e1a9365ce461895034bdb3 100644 (file)
--- a/gdb/doc/agentexpr.texi
+++ b/gdb/doc/agentexpr.texi
@@ -7,8 +7,7 @@
 
 @c This file is part of the GDB manual.
 @c
-@c Copyright (C) 2003, 2004, 2005, 2006, 2009, 2010, 2011
-@c Free Software Foundation, Inc.
+@c Copyright (C) 2003-2016 Free Software Foundation, Inc.
 @c
 @c See the file gdb.texinfo for copying conditions.
 
@@ -354,8 +353,7 @@ byte unsigned integer following the @code{ext} bytecode.
 
 @item @code{zero_ext} (0x2a) @var{n}: @var{a} @result{} @var{a}, zero-extended from @var{n} bits
 Pop an unsigned value from the stack; zero all but the bottom @var{n}
-bits.  This means that all bits to the left of bit @var{n-1} (where the
-least significant bit is bit 0) are set to the value of bit @var{n-1}.
+bits.
 
 The number of source bits to preserve, @var{n}, is encoded as a single
 byte unsigned integer following the @code{zero_ext} bytecode.
@@ -462,7 +460,7 @@ alignment within the bytecode stream; thus, on machines where fetching a
 16-bit on an unaligned address raises an exception, you should fetch the
 register number one byte at a time.
 
-@item @code{setv} (0x2d) @var{n}: @result{} @var{v}
+@item @code{setv} (0x2d) @var{n}: @var{v} @result{} @var{v}
 Set trace state variable number @var{n} to the value found on the top
 of the stack.  The stack is unchanged, so that the value is readily
 available if the assignment is part of a larger expression.  The
@@ -494,6 +492,23 @@ Record the bytes at @var{addr} in a trace buffer, for later retrieval
 by GDB.  Stop at either the first zero byte, or when @var{size} bytes
 have been recorded, whichever occurs first.
 
+@item @code{printf} (0x34)  @var{numargs} @var{string} @result{}
+Do a formatted print, in the style of the C function @code{printf}).
+The value of @var{numargs} is the number of arguments to expect on the
+stack, while @var{string} is the format string, prefixed with a
+two-byte length.  The last byte of the string must be zero, and is
+included in the length.  The format string includes escaped sequences
+just as it appears in C source, so for instance the format string
+@code{"\t%d\n"} is six characters long, and the output will consist of
+a tab character, a decimal number, and a newline.  At the top of the
+stack, above the values to be printed, this bytecode will pop a
+``function'' and ``channel''.  If the function is nonzero, then the
+target may treat it as a function and call it, passing the channel as
+a first argument, as with the C function @code{fprintf}.  If the
+function is zero, then the target may simply call a standard formatted
+print function of its choice.  In all, this bytecode pops 2 +
+@var{numargs} stack elements, and pushes nothing.
+
 @item @code{end} (0x27): @result{}
 Stop executing bytecode; the result should be the top element of the
 stack.  If the purpose of the expression was to compute an lvalue or a