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authorStephen Hines <srhines@google.com>2014-12-01 14:51:49 -0800
committerStephen Hines <srhines@google.com>2014-12-02 16:08:10 -0800
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Update aosp/master LLVM for rebase to r222494.
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+============================
+User Guide for R600 Back-end
+============================
+
+Introduction
+============
+
+The R600 back-end provides ISA code generation for AMD GPUs, starting with
+the R600 family up until the current Sea Islands (GCN Gen 2).
+
+
+Assembler
+=========
+
+The assembler is currently a work in progress and not yet complete. Below
+are the currently supported features.
+
+SOPP Instructions
+-----------------
+
+Unless otherwise mentioned, all SOPP instructions that with an operand
+accept a integer operand(s) only. No verification is performed on the
+operands, so it is up to the programmer to be familiar with the range
+or acceptable values.
+
+s_waitcnt
+^^^^^^^^^
+
+s_waitcnt accepts named arguments to specify which memory counter(s) to
+wait for.
+
+.. code-block:: nasm
+
+ // Wait for all counters to be 0
+ s_waitcnt 0
+
+ // Equivalent to s_waitcnt 0. Counter names can also be delimited by
+ // '&' or ','.
+ s_waitcnt vmcnt(0) expcnt(0) lgkcmt(0)
+
+ // Wait for vmcnt counter to be 1.
+ s_waitcnt vmcnt(1)
+