Enhanced the existing ARMExpandImm() and ThumbExpandImm() functions which expand
an imm12 into imm32 for ARM or Thumb so that they now handle carry_in/carry_out.
Funnel ARMExpandImm()/ThumbExpandImm() to the enhanced ARMExpandImm_C()/ThumbExpandImm_C()
functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvdb/trunk@125508 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Plugins/Process/Utility/ARMUtils.h b/source/Plugins/Process/Utility/ARMUtils.h
index e81de10..67125df 100644
--- a/source/Plugins/Process/Utility/ARMUtils.h
+++ b/source/Plugins/Process/Utility/ARMUtils.h
@@ -32,47 +32,78 @@
return (val >> m) | (val << (N - m));
}
+// (imm32, carry_out) = ARMExpandImm_C(imm12, carry_in)
+static inline uint32_t ARMExpandImm_C(uint32_t val, uint32_t carry_in, uint32_t &carry_out)
+{
+ uint32_t imm32; // the expanded result
+ uint32_t imm = bits(val, 7, 0); // immediate value
+ uint32_t amt = 2 * bits(val, 11, 8); // rotate amount
+ if (amt == 0)
+ {
+ imm32 = imm;
+ carry_out = carry_in;
+ }
+ else
+ {
+ imm32 = ror(imm, 32, amt);
+ carry_out = Bit32(imm32, 31);
+ }
+ return imm32;
+}
+
static inline uint32_t ARMExpandImm(uint32_t val)
{
- uint32_t imm = bits(val, 7, 0); // immediate value
- uint32_t rot = 2 * bits(val, 11, 8); // rotate amount
- return (imm >> rot) | (imm << (32 - rot));
+ // 'carry_in' argument to following function call does not affect the imm32 result.
+ uint32_t carry_in = 0;
+ uint32_t carry_out;
+ return ARMExpandImm_C(val, carry_in, carry_out);
+}
+
+// (imm32, carry_out) = ThumbExpandImm_C(imm12, carry_in)
+static inline uint32_t ThumbExpandImm_C(uint32_t val, uint32_t carry_in, uint32_t &carry_out)
+{
+ uint32_t imm32;
+ const uint32_t i = bit(val, 26);
+ const uint32_t imm3 = bits(val, 14, 12);
+ const uint32_t abcdefgh = bits(val, 7, 0);
+ const uint32_t imm12 = i << 11 | imm3 << 8 | abcdefgh;
+
+ if (bits(imm12, 11, 10) == 0)
+ {
+ switch (bits(imm12, 8, 9)) {
+ case 0:
+ imm32 = abcdefgh;
+ break;
+
+ case 1:
+ imm32 = abcdefgh << 16 | abcdefgh;
+ break;
+
+ case 2:
+ imm32 = abcdefgh << 24 | abcdefgh << 8;
+ break;
+
+ case 3:
+ imm32 = abcdefgh << 24 | abcdefgh << 16 | abcdefgh << 8 | abcdefgh;
+ break;
+ }
+ carry_out = carry_in;
+ }
+ else
+ {
+ const uint32_t unrotated_value = 0x80 | bits(imm12, 6, 0);
+ imm32 = ror(unrotated_value, 32, bits(imm12, 11, 7));
+ carry_out = Bit32(imm32, 31);
+ }
+ return imm32;
}
static inline uint32_t ThumbExpandImm(uint32_t val)
{
- uint32_t imm32 = 0;
- const uint32_t i = bit(val, 26);
- const uint32_t imm3 = bits(val, 14, 12);
- const uint32_t abcdefgh = bits(val, 7, 0);
- const uint32_t imm12 = i << 11 | imm3 << 8 | abcdefgh;
-
- if (bits(imm12, 10, 11) == 0)
- {
- switch (bits(imm12, 8, 9)) {
- case 0:
- imm32 = abcdefgh;
- break;
-
- case 1:
- imm32 = abcdefgh << 16 | abcdefgh;
- break;
-
- case 2:
- imm32 = abcdefgh << 24 | abcdefgh << 8;
- break;
-
- case 3:
- imm32 = abcdefgh << 24 | abcdefgh << 16 | abcdefgh << 8 | abcdefgh;
- break;
- }
- }
- else
- {
- const uint32_t unrotated_value = 0x80 | bits(imm12, 0, 6);
- imm32 = ror(unrotated_value, 32, bits(imm12, 7, 11));
- }
- return imm32;
+ // 'carry_in' argument to following function call does not affect the imm32 result.
+ uint32_t carry_in = 0;
+ uint32_t carry_out;
+ return ThumbExpandImm_C(val, carry_in, carry_out);
}
// imm32 = ZeroExtend(i:imm3:imm8, 32)