cparser/*: refactoring of the expansion of read-modify-write operators

cparser/PackedStructs: treat r-m-w operations over byte-swapped fields
cparser/PackedStructs: allow static initialization of packed structs
test/regression: more packedstruct tests


git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@1738 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e

5 files changed, 86 insertions, 5 deletions

diff --git a/test/regression/Makefile b/test/regression/Makefile
index 103901e..044e593 100644
--- a/test/regression/Makefile
+++ b/test/regression/Makefile
@@ -11,7 +11,7 @@ TESTS=attribs1 bitfields1 bitfields2 bitfields3 bitfields4 \
   bitfields5 bitfields6 bitfields7 \
   expr1 expr6 initializers volatile1 volatile2 volatile3 \
   funct3 expr5 struct7 struct8 struct11 casts1 casts2 char1 \
-  sizeof1 sizeof2 packedstruct1
+  sizeof1 sizeof2 packedstruct1 packedstruct2
 
 # Other tests: should compile to .s without errors (but expect warnings)
 EXTRAS=annot1 commaprec expr2 expr3 expr4 extern1 funct2 funptr1 init1 \
diff --git a/test/regression/Results/packedstruct1 b/test/regression/Results/packedstruct1
index 7549132..0595cc3 100644
--- a/test/regression/Results/packedstruct1
+++ b/test/regression/Results/packedstruct1
@@ -7,8 +7,9 @@ sizeof(struct s2) = 16
 offsetof(x) = 0, offsetof(y) = 2, offsetof(z) = 6
 s2 = {x = 57, y = -456, z = 3.14159}
 
-sizeof(struct s3) = 29
-s3 = {x = 123, y = 45678, z = 2147483649, v = -456, w = -1234567, p is ok, t = {111,222,333}}
+sizeof(struct s3) = 31
+offsetof(s) = 29
+s3 = {x = 123, y = 45678, z = 2147483649, v = -456, w = -1234567, p is ok, t = {111,222,333}, s = {'o','k'}}
 
 sizeof(struct s4) = 16
 offsetof(x) = 0, offsetof(y) = 4, offsetof(z) = 8
diff --git a/test/regression/Results/packedstruct2 b/test/regression/Results/packedstruct2
new file mode 100644
index 0000000..360a5c6
--- /dev/null
+++ b/test/regression/Results/packedstruct2
@@ -0,0 +1,6 @@
+s1 = {x = 2345, y = -12345678, z = 'x'}
+
+s3 = {x = 42, y = 123, z = 456789, v = -333, w = -314159, p is ok, t = {111,222,333}, s = {'o','k'}}
+
+s4 = {x = 123, y = -456789, z = 3.14159}
+
diff --git a/test/regression/packedstruct1.c b/test/regression/packedstruct1.c
index cecd1f3..66c8c9e 100644
--- a/test/regression/packedstruct1.c
+++ b/test/regression/packedstruct1.c
@@ -52,6 +52,7 @@ struct s3 {
   signed int w;
   char * p;
   unsigned int t[3];
+  unsigned char s[2];
 };
 
 struct s3 s3;
@@ -61,6 +62,7 @@ void test3(void)
   char xx;
 
   printf("sizeof(struct s3) = %d\n", sizeof(struct s3));
+  printf("offsetof(s) = %d\n", offsetof(s3,s));
   s3.x = 123;
   s3.y = 45678;
   s3.z = 0x80000001U;
@@ -70,10 +72,13 @@ void test3(void)
   s3.t[0] = 111;
   s3.t[1] = 222;
   s3.t[2] = 333;
-  printf("s3 = {x = %u, y = %u, z = %u, v = %d, w = %d, p is %s, t = {%d,%d,%d}}\n\n",
+  s3.s[0] = 'o';
+  s3.s[1] = 'k';
+  printf("s3 = {x = %u, y = %u, z = %u, v = %d, w = %d, p is %s, t = {%d,%d,%d}, s = {'%c','%c'}}\n\n",
          s3.x, s3.y, s3.z, s3.v, s3.w,
          (s3.p == &xx ? "ok" : "BAD"),
-         s3.t[0], s3.t[1], s3.t[2]);
+         s3.t[0], s3.t[1], s3.t[2],
+         s3.s[0], s3.s[1]);
 }
 
 /* Back to normal */
diff --git a/test/regression/packedstruct2.c b/test/regression/packedstruct2.c
new file mode 100644
index 0000000..0c383a4
--- /dev/null
+++ b/test/regression/packedstruct2.c
@@ -0,0 +1,69 @@
+/* Initialization of packed structs */
+
+#include <stdio.h>
+
+/* Simple packing */
+
+#pragma pack(1)
+
+struct s1 { unsigned short x; int y; char z; };
+
+struct s1 s1 = { 2345, -12345678, 'x' };
+
+void test1(void)
+{
+  printf("s1 = {x = %d, y = %d, z = '%c'}\n\n", s1.x, s1.y, s1.z);
+}
+
+/* Now with byte-swapped fields */
+
+#pragma pack(1,1,1)
+
+struct s3 {
+  unsigned char x; 
+  unsigned short y;
+  unsigned int z;
+  signed short v;
+  signed int w;
+  char * p;
+  unsigned int t[3];
+  unsigned char s[2];
+};
+
+struct s3 s3 = {
+  42, 123, 456789, -333, -314159, 0, 
+  { 111, 222, 333 },
+  { 'o', 'k' }
+};
+
+void test3(void)
+{
+  printf("s3 = {x = %u, y = %u, z = %u, v = %d, w = %d, p is %s, t = {%d,%d,%d}, s = {'%c','%c'}}\n\n",
+         s3.x, s3.y, s3.z, s3.v, s3.w,
+         (s3.p == 0 ? "ok" : "BAD"),
+         s3.t[0], s3.t[1], s3.t[2],
+         s3.s[0], s3.s[1]);
+}
+
+/* Back to normal */
+
+#pragma pack()
+
+struct s4 { unsigned short x; int y; double z; };
+
+struct s4 s4 = { 123, -456789, 3.14159 };
+
+void test4(void)
+{
+  printf("s4 = {x = %d, y = %d, z = %.5f}\n\n", s4.x, s4.y, s4.z);
+}
+
+/* Test harness */
+
+int main(int argc, char ** argv)
+{
+  test1();
+  test3();
+  test4();
+  return 0;
+}