-- * Regs.h claims that BaseReg should be saved last and loaded first
-- * This might not have been tickled before since BaseReg is callee save
-- * Regs.h saves SparkHd, ParkT1, SparkBase and SparkLim
+-- EZY: This code is very dodgy, because callerSaves only ever
+-- returns true in the current universe for registers NOT in
+-- system_regs (just do a grep for CALLER_SAVES in
+-- includes/stg/MachRegs.h). Thus, this is all one giant no-op. What we are
+-- actually interested in is saving are the non-system registers, which
+-- we is what the old code generator actually does at this point.
+-- Unfortunately, we can't do that here either, because we don't
+-- liveness information, and thus there's not an easy way to tell which
+-- specific global registers need to be saved (the 'vols' argument in
+-- the old code generator.) One possible hack is to save all of them
+-- unconditionally, but unless we have very clever dead /memory/
+-- elimination (unlikely), this will still leave a dead, unnecessary
+-- memory assignment. And really, we shouldn't be doing the workaround
+-- at this point in the pipeline, see Note [Register parameter passing].
+-- Right now the workaround is to avoid inlining across unsafe foreign
+-- calls in rewriteAssignments.
callerSaveVolatileRegs :: (CmmAGraph, CmmAGraph)
callerSaveVolatileRegs = (caller_save, caller_load)
where
#ifdef CALLER_SAVES_Base
callerSaves BaseReg = True
#endif
+#ifdef CALLER_SAVES_R1
+callerSaves (VanillaReg 1 _) = True
+#endif
+#ifdef CALLER_SAVES_R2
+callerSaves (VanillaReg 2 _) = True
+#endif
+#ifdef CALLER_SAVES_R3
+callerSaves (VanillaReg 3 _) = True
+#endif
+#ifdef CALLER_SAVES_R4
+callerSaves (VanillaReg 4 _) = True
+#endif
+#ifdef CALLER_SAVES_R5
+callerSaves (VanillaReg 5 _) = True
+#endif
+#ifdef CALLER_SAVES_R6
+callerSaves (VanillaReg 6 _) = True
+#endif
+#ifdef CALLER_SAVES_R7
+callerSaves (VanillaReg 7 _) = True
+#endif
+#ifdef CALLER_SAVES_R8
+callerSaves (VanillaReg 8 _) = True
+#endif
+#ifdef CALLER_SAVES_F1
+callerSaves (FloatReg 1) = True
+#endif
+#ifdef CALLER_SAVES_F2
+callerSaves (FloatReg 2) = True
+#endif
+#ifdef CALLER_SAVES_F3
+callerSaves (FloatReg 3) = True
+#endif
+#ifdef CALLER_SAVES_F4
+callerSaves (FloatReg 4) = True
+#endif
+#ifdef CALLER_SAVES_D1
+callerSaves (DoubleReg 1) = True
+#endif
+#ifdef CALLER_SAVES_D2
+callerSaves (DoubleReg 2) = True
+#endif
+#ifdef CALLER_SAVES_L1
+callerSaves (LongReg 1) = True
+#endif
#ifdef CALLER_SAVES_Sp
callerSaves Sp = True
#endif