Merge pull request #2132 from jhogberg/john/compiler/tuple-element-types

Keep track of tuple elements in type optimization pass

1 files changed, 6 insertions, 5 deletions

diff --git a/lib/compiler/src/beam_ssa_pre_codegen.erl b/lib/compiler/src/beam_ssa_pre_codegen.erl
index 274f78052d..ad57a45ef2 100644
--- a/lib/compiler/src/beam_ssa_pre_codegen.erl
+++ b/lib/compiler/src/beam_ssa_pre_codegen.erl
@@ -1993,11 +1993,12 @@ reserve_zregs(Blocks, Intervals, Res) ->
         end,
     beam_ssa:fold_rpo(F, [0], Res, Blocks).
 
-reserve_zreg([#b_set{op=call,dst=Dst}],
-              #b_br{bool=Dst}, _ShortLived, A) ->
-    %% If type optimization has determined that the result of a call can be
-    %% used directly in a branch, we must avoid reserving a z register or code
-    %% generation will fail.
+reserve_zreg([#b_set{op=Op,dst=Dst}],
+              #b_br{bool=Dst}, _ShortLived, A) when Op =:= call;
+                                                    Op =:= get_tuple_element ->
+    %% If type optimization has determined that the result of these
+    %% instructions can be used directly in a branch, we must avoid reserving a
+    %% z register or code generation will fail.
     A;
 reserve_zreg([#b_set{op={bif,tuple_size},dst=Dst},
               #b_set{op={bif,'=:='},args=[Dst,Val]}], Last, ShortLived, A0) ->