Fix warm-start of bipartite methods

Applies to BiLQR and TriLQR (only in cases of wrong input sizes) and to
TriCG, TriMR, and GPMR where `x0` and `y0` had their sizes swapped.

Author: timholy

src/workspace_accessors.jl

@@ -153,10 +153,10 @@ for (KS, fun, nsol, nA, nAt, warm_start) in [
       issolved(workspace :: $KS) = workspace.stats.solved
     end
     if $warm_start
-      if $KS in (BilqrWorkspace, TrilqrWorkspace, TricgWorkspace, TrimrWorkspace, GpmrWorkspace)
+      if $KS in (BilqrWorkspace, TrilqrWorkspace)
         function warm_start!(workspace :: $KS, x0, y0)
-          length(x0) == workspace.n || error("x0 should have size $n")
-          length(y0) == workspace.m || error("y0 should have size $m")
+          length(x0) == workspace.n || error("x0 should have size $(workspace.n)")
+          length(y0) == workspace.m || error("y0 should have size $(workspace.m)")
           S = typeof(workspace.x)
           allocate_if(true, workspace, :Δx, S, workspace.x)  # The length of Δx is n
           allocate_if(true, workspace, :Δy, S, workspace.y)  # The length of Δy is m
@@ -165,6 +165,18 @@ for (KS, fun, nsol, nA, nAt, warm_start) in [
           workspace.warm_start = true
           return workspace
         end
+      elseif $KS in (TricgWorkspace, TrimrWorkspace, GpmrWorkspace)
+        function warm_start!(workspace :: $KS, x0, y0)
+          length(x0) == workspace.m || error("x0 should have size $(workspace.m)")
+          length(y0) == workspace.n || error("y0 should have size $(workspace.n)")
+          S = typeof(workspace.x)
+          allocate_if(true, workspace, :Δx, S, workspace.x)  # The length of Δx is m
+          allocate_if(true, workspace, :Δy, S, workspace.y)  # The length of Δy is n
+          kcopy!(workspace.m, workspace.Δx, x0)
+          kcopy!(workspace.n, workspace.Δy, y0)
+          workspace.warm_start = true
+          return workspace
+        end
       else
         function warm_start!(workspace :: $KS, x0)
           S = typeof(workspace.x)