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llvm-svn: 25843

llvm/lib/Target/SparcV8/README.txt

@@ -7,4 +7,33 @@ To-do
 * We can fold small constant offsets into the %hi/%lo references to constant
   pool addresses as well.
 * When in V9 mode, register allocate %icc[0-3].
+* Emit the 'Branch on Integer Register with Prediction' instructions.  It's
+  not clear how to write a pattern for this though:
+
+float %t1(int %a, int* %p) {
+        %C = seteq int %a, 0
+        br bool %C, label %T, label %F
+T:
+        store int 123, int* %p
+        br label %F
+F:
+        ret float undef
+}
+
+codegens to this:
+
+t1:
+        save -96, %o6, %o6
+1)      subcc %i0, 0, %l0
+1)      bne .LBBt1_2    ! F
+        nop
+.LBBt1_1:       ! T
+        or %g0, 123, %l0
+        st %l0, [%i1]
+.LBBt1_2:       ! F
+        restore %g0, %g0, %g0
+        retl
+        nop
+
+1) should be replaced with a brz in V9 mode.