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Diffstat (limited to 'target-arm/op_helper.c')
-rw-r--r--target-arm/op_helper.c148
1 files changed, 148 insertions, 0 deletions
diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c
index 6748b0605..79b3f1a45 100644
--- a/target-arm/op_helper.c
+++ b/target-arm/op_helper.c
@@ -304,3 +304,151 @@ void HELPER(set_user_reg)(uint32_t regno, uint32_t val)
}
}
+/* ??? Flag setting arithmetic is awkward because we need to do comparisons.
+ The only way to do that in TCG is a conditional branch, which clobbers
+ all our temporaries. For now implement these as helper functions. */
+
+uint32_t HELPER (add_cc)(uint32_t a, uint32_t b)
+{
+ uint32_t result;
+ result = T0 + T1;
+ env->NZF = result;
+ env->CF = result < a;
+ env->VF = (a ^ b ^ -1) & (a ^ result);
+ return result;
+}
+
+uint32_t HELPER(adc_cc)(uint32_t a, uint32_t b)
+{
+ uint32_t result;
+ if (!env->CF) {
+ result = a + b;
+ env->CF = result < a;
+ } else {
+ result = a + b + 1;
+ env->CF = result <= a;
+ }
+ env->VF = (a ^ b ^ -1) & (a ^ result);
+ env->NZF = result;
+ return result;
+}
+
+uint32_t HELPER(sub_cc)(uint32_t a, uint32_t b)
+{
+ uint32_t result;
+ result = a - b;
+ env->NZF = result;
+ env->CF = a >= b;
+ env->VF = (a ^ b) & (a ^ result);
+ return result;
+}
+
+uint32_t HELPER(sbc_cc)(uint32_t a, uint32_t b)
+{
+ uint32_t result;
+ if (!env->CF) {
+ result = a - b - 1;
+ env->CF = a > b;
+ } else {
+ result = a - b;
+ env->CF = a >= b;
+ }
+ env->VF = (a ^ b) & (a ^ result);
+ env->NZF = result;
+ return result;
+}
+
+/* Similarly for variable shift instructions. */
+
+uint32_t HELPER(shl)(uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32)
+ return 0;
+ return x << shift;
+}
+
+uint32_t HELPER(shr)(uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32)
+ return 0;
+ return (uint32_t)x >> shift;
+}
+
+uint32_t HELPER(sar)(uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32)
+ shift = 31;
+ return (int32_t)x >> shift;
+}
+
+uint32_t HELPER(ror)(uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift == 0)
+ return x;
+ return (x >> shift) | (x << (32 - shift));
+}
+
+uint32_t HELPER(shl_cc)(uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32) {
+ if (shift == 32)
+ env->CF = x & 1;
+ else
+ env->CF = 0;
+ return 0;
+ } else if (shift != 0) {
+ env->CF = (x >> (32 - shift)) & 1;
+ return x << shift;
+ }
+ return x;
+}
+
+uint32_t HELPER(shr_cc)(uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32) {
+ if (shift == 32)
+ env->CF = (x >> 31) & 1;
+ else
+ env->CF = 0;
+ return 0;
+ } else if (shift != 0) {
+ env->CF = (x >> (shift - 1)) & 1;
+ return x >> shift;
+ }
+ return x;
+}
+
+uint32_t HELPER(sar_cc)(uint32_t x, uint32_t i)
+{
+ int shift = i & 0xff;
+ if (shift >= 32) {
+ env->CF = (x >> 31) & 1;
+ return (int32_t)x >> 31;
+ } else if (shift != 0) {
+ env->CF = (x >> (shift - 1)) & 1;
+ return (int32_t)x >> shift;
+ }
+ return x;
+}
+
+uint32_t HELPER(ror_cc)(uint32_t x, uint32_t i)
+{
+ int shift1, shift;
+ shift1 = i & 0xff;
+ shift = shift1 & 0x1f;
+ if (shift == 0) {
+ if (shift1 != 0)
+ env->CF = (x >> 31) & 1;
+ return x;
+ } else {
+ env->CF = (x >> (shift - 1)) & 1;
+ return ((uint32_t)x >> shift) | (x << (32 - shift));
+ }
+}
+