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[ARM, AArch64] Make aarch64-common.c files more robust.


Hi,

Recently I've found myself getting a number of segfaults from
code calling in to the arm_early_load/alu_dep functions in
aarch64-common.c. These functions expect a particular form
for the RTX patterns they work over, but some of them do
not validate this form.

This patch fixes that, removing segmentation faults I see
when tuning for Cortex-A15 and Cortex-A7.

Tested on aarch64-none-elf and arm-none-eabi with no regressions.

OK?

Thanks,
James

---
gcc/

2013-09-30  James Greenhalgh  <james.greenhalgh@arm.com>

	* config/arm/aarch-common.c
	(arm_early_load_addr_dep): Add sanity checking.
	(arm_no_early_alu_shift_dep): Likewise.
	(arm_no_early_alu_shift_value_dep): Likewise.
	(arm_no_early_mul_dep): Likewise.
	(arm_no_early_store_addr_dep): Likewise.
diff --git a/gcc/config/arm/aarch-common.c b/gcc/config/arm/aarch-common.c
index 69366af..ea50848 100644
--- a/gcc/config/arm/aarch-common.c
+++ b/gcc/config/arm/aarch-common.c
@@ -44,7 +44,12 @@ arm_early_load_addr_dep (rtx producer, rtx consumer)
     value = COND_EXEC_CODE (value);
   if (GET_CODE (value) == PARALLEL)
     value = XVECEXP (value, 0, 0);
+
+  if (GET_CODE (value) != SET)
+    return 0;
+
   value = XEXP (value, 0);
+
   if (GET_CODE (addr) == COND_EXEC)
     addr = COND_EXEC_CODE (addr);
   if (GET_CODE (addr) == PARALLEL)
@@ -54,6 +59,10 @@ arm_early_load_addr_dep (rtx producer, rtx consumer)
       else
         addr = XVECEXP (addr, 0, 0);
     }
+
+  if (GET_CODE (addr) != SET)
+    return 0;
+
   addr = XEXP (addr, 1);
 
   return reg_overlap_mentioned_p (value, addr);
@@ -74,21 +83,41 @@ arm_no_early_alu_shift_dep (rtx producer, rtx consumer)
     value = COND_EXEC_CODE (value);
   if (GET_CODE (value) == PARALLEL)
     value = XVECEXP (value, 0, 0);
+
+  if (GET_CODE (value) != SET)
+    return 0;
+
   value = XEXP (value, 0);
+
   if (GET_CODE (op) == COND_EXEC)
     op = COND_EXEC_CODE (op);
   if (GET_CODE (op) == PARALLEL)
     op = XVECEXP (op, 0, 0);
+
+  if (GET_CODE (op) != SET)
+    return 0;
+
   op = XEXP (op, 1);
 
+  if (!INSN_P (op))
+    return 0;
+
   early_op = XEXP (op, 0);
+
   /* This is either an actual independent shift, or a shift applied to
      the first operand of another operation.  We want the whole shift
      operation.  */
   if (REG_P (early_op))
     early_op = op;
 
-  return !reg_overlap_mentioned_p (value, early_op);
+  if (GET_CODE (op) == ASHIFT
+      || GET_CODE (op) == ROTATE
+      || GET_CODE (op) == ASHIFTRT
+      || GET_CODE (op) == LSHIFTRT
+      || GET_CODE (op) == ROTATERT)
+    return !reg_overlap_mentioned_p (value, early_op);
+  else
+    return 0;
 }
 
 /* Return nonzero if the CONSUMER instruction (an ALU op) does not
@@ -106,13 +135,25 @@ arm_no_early_alu_shift_value_dep (rtx producer, rtx consumer)
     value = COND_EXEC_CODE (value);
   if (GET_CODE (value) == PARALLEL)
     value = XVECEXP (value, 0, 0);
+
+  if (GET_CODE (value) != SET)
+    return 0;
+
   value = XEXP (value, 0);
+
   if (GET_CODE (op) == COND_EXEC)
     op = COND_EXEC_CODE (op);
   if (GET_CODE (op) == PARALLEL)
     op = XVECEXP (op, 0, 0);
+
+  if (GET_CODE (op) != SET)
+    return 0;
+
   op = XEXP (op, 1);
 
+  if (!INSN_P (op))
+    return 0;
+
   early_op = XEXP (op, 0);
 
   /* This is either an actual independent shift, or a shift applied to
@@ -121,7 +162,14 @@ arm_no_early_alu_shift_value_dep (rtx producer, rtx consumer)
   if (!REG_P (early_op))
     early_op = XEXP (early_op, 0);
 
-  return !reg_overlap_mentioned_p (value, early_op);
+  if (GET_CODE (op) == ASHIFT
+      || GET_CODE (op) == ROTATE
+      || GET_CODE (op) == ASHIFTRT
+      || GET_CODE (op) == LSHIFTRT
+      || GET_CODE (op) == ROTATERT)
+    return !reg_overlap_mentioned_p (value, early_op);
+  else
+    return 0;
 }
 
 /* Return nonzero if the CONSUMER (a mul or mac op) does not
@@ -138,11 +186,20 @@ arm_no_early_mul_dep (rtx producer, rtx consumer)
     value = COND_EXEC_CODE (value);
   if (GET_CODE (value) == PARALLEL)
     value = XVECEXP (value, 0, 0);
+
+  if (GET_CODE (value) != SET)
+    return 0;
+
   value = XEXP (value, 0);
+
   if (GET_CODE (op) == COND_EXEC)
     op = COND_EXEC_CODE (op);
   if (GET_CODE (op) == PARALLEL)
     op = XVECEXP (op, 0, 0);
+
+  if (GET_CODE (op) != SET)
+    return 0;
+
   op = XEXP (op, 1);
 
   if (GET_CODE (op) == PLUS || GET_CODE (op) == MINUS)
@@ -169,11 +226,20 @@ arm_no_early_store_addr_dep (rtx producer, rtx consumer)
     value = COND_EXEC_CODE (value);
   if (GET_CODE (value) == PARALLEL)
     value = XVECEXP (value, 0, 0);
+
+  if (GET_CODE (value) != SET)
+    return 0;
+
   value = XEXP (value, 0);
+
   if (GET_CODE (addr) == COND_EXEC)
     addr = COND_EXEC_CODE (addr);
   if (GET_CODE (addr) == PARALLEL)
     addr = XVECEXP (addr, 0, 0);
+
+  if (GET_CODE (addr) != SET)
+    return 0;
+
   addr = XEXP (addr, 0);
 
   return !reg_overlap_mentioned_p (value, addr);

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