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[5/9] Create sensible dummy registers
- From: Richard Sandiford <richard dot sandiford at arm dot com>
- To: gcc-patches at gcc dot gnu dot org
- Date: Mon, 18 May 2015 19:21:59 +0100
- Subject: [5/9] Create sensible dummy registers
- Authentication-results: sourceware.org; auth=none
- References: <87oalhu59s dot fsf at e105548-lin dot cambridge dot arm dot com>
Some pieces of code create a temporary REG or MEM and only fill it
in later when they're testing the cost of a particular rtx. This patch
makes sure that even the dummy REG or MEM is valid, rather than force
the gen_* code to handle garbage values.
gcc/
* caller-save.c (init_caller_save): Use word_mode and
FIRST_PSEUDO_REGISTER when creating temporary rtxes.
* expr.c (init_expr_target): Likewise.
* ira.c (setup_prohibited_mode_move_regs): Likewise.
* postreload.c (reload_cse_regs_1): Likewise.
Index: gcc/caller-save.c
===================================================================
--- gcc/caller-save.c 2015-05-16 15:50:58.063567104 +0100
+++ gcc/caller-save.c 2015-05-16 15:50:58.055567198 +0100
@@ -287,8 +287,8 @@ init_caller_save (void)
To avoid lots of unnecessary RTL allocation, we construct all the RTL
once, then modify the memory and register operands in-place. */
- test_reg = gen_rtx_REG (VOIDmode, 0);
- test_mem = gen_rtx_MEM (VOIDmode, address);
+ test_reg = gen_rtx_REG (word_mode, FIRST_PSEUDO_REGISTER);
+ test_mem = gen_rtx_MEM (word_mode, address);
savepat = gen_rtx_SET (test_mem, test_reg);
restpat = gen_rtx_SET (test_reg, test_mem);
Index: gcc/expr.c
===================================================================
--- gcc/expr.c 2015-05-16 15:50:58.063567104 +0100
+++ gcc/expr.c 2015-05-16 15:50:58.059567152 +0100
@@ -202,12 +202,12 @@ init_expr_target (void)
/* Try indexing by frame ptr and try by stack ptr.
It is known that on the Convex the stack ptr isn't a valid index.
With luck, one or the other is valid on any machine. */
- mem = gen_rtx_MEM (VOIDmode, stack_pointer_rtx);
- mem1 = gen_rtx_MEM (VOIDmode, frame_pointer_rtx);
+ mem = gen_rtx_MEM (word_mode, stack_pointer_rtx);
+ mem1 = gen_rtx_MEM (word_mode, frame_pointer_rtx);
/* A scratch register we can modify in-place below to avoid
useless RTL allocations. */
- reg = gen_rtx_REG (VOIDmode, -1);
+ reg = gen_rtx_REG (word_mode, FIRST_PSEUDO_REGISTER);
insn = rtx_alloc (INSN);
pat = gen_rtx_SET (NULL_RTX, NULL_RTX);
Index: gcc/ira.c
===================================================================
--- gcc/ira.c 2015-05-16 15:50:58.063567104 +0100
+++ gcc/ira.c 2015-05-16 15:50:58.055567198 +0100
@@ -1767,8 +1767,8 @@ setup_prohibited_mode_move_regs (void)
if (ira_prohibited_mode_move_regs_initialized_p)
return;
ira_prohibited_mode_move_regs_initialized_p = true;
- test_reg1 = gen_rtx_REG (VOIDmode, 0);
- test_reg2 = gen_rtx_REG (VOIDmode, 0);
+ test_reg1 = gen_rtx_REG (word_mode, FIRST_PSEUDO_REGISTER);
+ test_reg2 = gen_rtx_REG (word_mode, FIRST_PSEUDO_REGISTER);
move_pat = gen_rtx_SET (test_reg1, test_reg2);
move_insn = gen_rtx_INSN (VOIDmode, 0, 0, 0, move_pat, 0, -1, 0);
for (i = 0; i < NUM_MACHINE_MODES; i++)
Index: gcc/postreload.c
===================================================================
--- gcc/postreload.c 2015-05-16 15:50:58.063567104 +0100
+++ gcc/postreload.c 2015-05-16 15:50:58.055567198 +0100
@@ -234,7 +234,7 @@ reload_cse_regs_1 (void)
bool cfg_changed = false;
basic_block bb;
rtx_insn *insn;
- rtx testreg = gen_rtx_REG (VOIDmode, -1);
+ rtx testreg = gen_rtx_REG (word_mode, FIRST_PSEUDO_REGISTER);
cselib_init (CSELIB_RECORD_MEMORY);
init_alias_analysis ();