[PATCH] Hexagon (target/hexagon) put writes to USR into temp until commit

[Taylor Simpson]

Change SET_USR_FIELD to write to hex_new_value[HEX_REG_USR] instead
of hex_gpr[HEX_REG_USR].

Then, we need code to mark the instructions that can set implicitly
set USR
- Macros added to hex_common.py
- A_FPOP added in translate.c

Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
---
 target/hexagon/macros.h          | 2 +-
 target/hexagon/attribs_def.h.inc | 1 +
 target/hexagon/translate.c       | 9 ++++++++-
 target/hexagon/hex_common.py     | 2 ++
 4 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/target/hexagon/macros.h b/target/hexagon/macros.h
index 094b8da..c0e2d7c 100644
--- a/target/hexagon/macros.h
+++ b/target/hexagon/macros.h
@@ -62,7 +62,7 @@
                    reg_field_info[FIELD].offset)
 
 #define SET_USR_FIELD(FIELD, VAL) \
-    fINSERT_BITS(env->gpr[HEX_REG_USR], reg_field_info[FIELD].width, \
+    fINSERT_BITS(env->new_value[HEX_REG_USR], reg_field_info[FIELD].width, \
                  reg_field_info[FIELD].offset, (VAL))
 #endif
 
diff --git a/target/hexagon/attribs_def.h.inc b/target/hexagon/attribs_def.h.inc
index 3815509..e44a7ea 100644
--- a/target/hexagon/attribs_def.h.inc
+++ b/target/hexagon/attribs_def.h.inc
@@ -64,6 +64,7 @@ DEF_ATTRIB(IMPLICIT_WRITES_P1, "Writes Predicate 1", "", 
"UREG.P1")
 DEF_ATTRIB(IMPLICIT_WRITES_P2, "Writes Predicate 1", "", "UREG.P2")
 DEF_ATTRIB(IMPLICIT_WRITES_P3, "May write Predicate 3", "", "UREG.P3")
 DEF_ATTRIB(IMPLICIT_READS_PC, "Reads the PC register", "", "")
+DEF_ATTRIB(IMPLICIT_WRITES_USR, "May write USR", "", "")
 DEF_ATTRIB(WRITES_PRED_REG, "Writes a predicate register", "", "")
 
 DEF_ATTRIB(CRSLOT23, "Can execute in slot 2 or slot 3 (CR)", "", "")
diff --git a/target/hexagon/translate.c b/target/hexagon/translate.c
index 6fb4e68..2c9081a 100644
--- a/target/hexagon/translate.c
+++ b/target/hexagon/translate.c
@@ -210,7 +210,12 @@ static void mark_implicit_reg_write(DisasContext *ctx, 
Insn *insn,
                                     int attrib, int rnum)
 {
     if (GET_ATTRIB(insn->opcode, attrib)) {
-        bool is_predicated = GET_ATTRIB(insn->opcode, A_CONDEXEC);
+        /*
+         * USR is used to set overflow and FP exceptions,
+         * so treat it as conditional
+         */
+        bool is_predicated = GET_ATTRIB(insn->opcode, A_CONDEXEC) ||
+                             rnum == HEX_REG_USR;
         if (is_predicated && !is_preloaded(ctx, rnum)) {
             tcg_gen_mov_tl(hex_new_value[rnum], hex_gpr[rnum]);
         }
@@ -236,6 +241,8 @@ static void mark_implicit_reg_writes(DisasContext *ctx, 
Insn *insn)
     mark_implicit_reg_write(ctx, insn, A_IMPLICIT_WRITES_SA0, HEX_REG_SA0);
     mark_implicit_reg_write(ctx, insn, A_IMPLICIT_WRITES_LC1, HEX_REG_LC1);
     mark_implicit_reg_write(ctx, insn, A_IMPLICIT_WRITES_SA1, HEX_REG_SA1);
+    mark_implicit_reg_write(ctx, insn, A_IMPLICIT_WRITES_USR, HEX_REG_USR);
+    mark_implicit_reg_write(ctx, insn, A_FPOP, HEX_REG_USR);
 }
 
 static void mark_implicit_pred_writes(DisasContext *ctx, Insn *insn)
diff --git a/target/hexagon/hex_common.py b/target/hexagon/hex_common.py
index b3b5340..a84b003 100755
--- a/target/hexagon/hex_common.py
+++ b/target/hexagon/hex_common.py
@@ -73,6 +73,8 @@ def calculate_attribs():
     add_qemu_macro_attrib('fWRITE_P1', 'A_WRITES_PRED_REG')
     add_qemu_macro_attrib('fWRITE_P2', 'A_WRITES_PRED_REG')
     add_qemu_macro_attrib('fWRITE_P3', 'A_WRITES_PRED_REG')
+    add_qemu_macro_attrib('fSET_OVERFLOW', 'A_IMPLICIT_WRITES_USR')
+    add_qemu_macro_attrib('fSET_LPCFG', 'A_IMPLICIT_WRITES_USR')
 
     # Recurse down macros, find attributes from sub-macros
     macroValues = list(macros.values())
-- 
2.7.4