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[PING][PATCH] Fix for PR 61561

This is a reminder message on fix for PR 61561 which is ICE while compiling something which is valid* 'C' code. (

Ramana, Richard, I am very appreciated for your attention and error indication, your work made my patch simple and tiny. And I hope that this patch will save somebody's time.

Additional info about the issue:

By adding constrain 'k' we want to make gcc work properly with stack register in HI and QI mode. This is need because CSE an RTL phase in some cases propagates sp register directly to HI/QI memory set. Next reload an RTL phase trying to build HI/QI move sp into some general purpose register which is fail due to pattern absence. You may ask who needs part of sp register? Nevertheless it is legitimate operation and there is simple example of practical usage. Imagine you put some local variable 'a' into hash table which has < 256 bunches. In this case 'operator []' of some hash class may take QI from sp register which is directly pointing on 'a'.

Patch was reg. tested on --build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu --target=arm-v7a15v5r2-linux-gnueabi for c,c++,fortran languages w/o bootstrap.

* According to 'C' Standard [ISO/IEC 9899:2011]
"Any pointer type may be converted to an integer type. Except as previously specified, the result is implementation-defined". As we know 'char' and 'short' (also called 'short int') are both integers.

Thank for your attention.


2014-06-30  Marat Zakirov  <>

	PR target/61561
	* config/arm/ (*movhi_insn_arch4): Handle stack pointer.
	(*movhi_bytes): Likewise.
	(*arm_movqi_insn): Likewise. 


2014-06-30  Marat Zakirov  <>

	PR target/61561
	* gcc.dg/pr61561.c: New test.

diff --git a/gcc/config/arm/ b/gcc/config/arm/
index 42c12c8..99290dc 100644
--- a/gcc/config/arm/
+++ b/gcc/config/arm/
@@ -6291,7 +6291,7 @@
 ;; Pattern to recognize insn generated default case above
 (define_insn "*movhi_insn_arch4"
   [(set (match_operand:HI 0 "nonimmediate_operand" "=r,r,m,r")
-	(match_operand:HI 1 "general_operand"      "rI,K,r,mi"))]
+	(match_operand:HI 1 "general_operand"      "rIk,K,r,mi"))]
    && arm_arch4
    && (register_operand (operands[0], HImode)
@@ -6315,7 +6315,7 @@
 (define_insn "*movhi_bytes"
   [(set (match_operand:HI 0 "s_register_operand" "=r,r,r")
-	(match_operand:HI 1 "arm_rhs_operand"  "I,r,K"))]
+	(match_operand:HI 1 "arm_rhs_operand"  "I,rk,K"))]
    mov%?\\t%0, %1\\t%@ movhi
@@ -6430,7 +6430,7 @@
 (define_insn "*arm_movqi_insn"
   [(set (match_operand:QI 0 "nonimmediate_operand" "=r,r,r,l,r,l,Uu,r,m")
-	(match_operand:QI 1 "general_operand" "r,r,I,Py,K,Uu,l,m,r"))]
+	(match_operand:QI 1 "general_operand" "rk,rk,I,Py,K,Uu,l,m,r"))]
    && (   register_operand (operands[0], QImode)
        || register_operand (operands[1], QImode))"
diff --git a/gcc/testsuite/gcc.dg/pr61561.c b/gcc/testsuite/gcc.dg/pr61561.c
new file mode 100644
index 0000000..0f4b716
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr61561.c
@@ -0,0 +1,15 @@
+/* PR c/61561.  */
+/* { dg-do assemble } */
+/* { dg-options " -w -O2" } */
+int dummy (int a);
+char a;
+short b;
+void mmm (void)
+  char dyn[dummy (3)];
+  a = (char)&dyn[0];
+  b = (short)&dyn[0];

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