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| author | Christoph Müllner <christoph.muellner@vrull.eu> | 2022-06-28 17:44:15 +0200 |
|---|---|---|
| committer | Philipp Tomsich <philipp.tomsich@vrull.eu> | 2022-09-22 18:06:09 +0200 |
| commit | 8b7419c429919884adced1fd2eae8c805b45b49a (patch) | |
| tree | 0ac96804e7726bb8ff28a03a429309f3a9e0665b /include | |
| parent | 547c18d9bb95571261dbd17f4767194037eb82bd (diff) | |
| download | gdb-8b7419c429919884adced1fd2eae8c805b45b49a.zip gdb-8b7419c429919884adced1fd2eae8c805b45b49a.tar.gz gdb-8b7419c429919884adced1fd2eae8c805b45b49a.tar.bz2 | |
RISC-V: Add support for arbitrary immediate encoding formats
This patch introduces support for arbitrary signed or unsigned immediate
encoding formats. The formats have the form "XsN@S" and "XuN@S" with N
being the number of bits and S the LSB position.
For example an immediate field of 5 bytes that encodes a signed value
and is stored in the bits 24-20 of the instruction word can use the
format specifier "Xs5@20".
Co-developed-by: Lifang Xia <lifang_xia@linux.alibaba.com>
Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
Diffstat (limited to 'include')
| -rw-r--r-- | include/opcode/riscv.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/include/opcode/riscv.h b/include/opcode/riscv.h index 6fdc9c9..faef28a 100644 --- a/include/opcode/riscv.h +++ b/include/opcode/riscv.h @@ -60,6 +60,7 @@ static const char * const riscv_pred_succ[16] = #define RV_X(x, s, n) (((x) >> (s)) & ((1 << (n)) - 1)) #define RV_IMM_SIGN(x) (-(((x) >> 31) & 1)) +#define RV_X_SIGNED(x, s, n) (RV_X(x, s, n) | ((-(RV_X(x, (s + n - 1), 1))) << (n))) #define EXTRACT_ITYPE_IMM(x) \ (RV_X(x, 20, 12) | (RV_IMM_SIGN(x) << 12)) @@ -347,6 +348,22 @@ static const char * const riscv_pred_succ[16] = #define EXTRACT_OPERAND(FIELD, INSN) \ EXTRACT_BITS ((INSN), OP_MASK_##FIELD, OP_SH_##FIELD) +/* Extract an unsigned immediate operand on position s with n bits. */ +#define EXTRACT_U_IMM(n, s, l) \ + RV_X (l, s, n) + +/* Extract an signed immediate operand on position s with n bits. */ +#define EXTRACT_S_IMM(n, s, l) \ + RV_X_SIGNED (l, s, n) + +/* Validate that unsigned n-bit immediate is within bounds. */ +#define VALIDATE_U_IMM(v, n) \ + ((unsigned long) v < (1UL << n)) + +/* Validate that signed n-bit immediate is within bounds. */ +#define VALIDATE_S_IMM(v, n) \ + (v < (long) (1UL << (n-1)) && v >= -(offsetT) (1UL << (n-1))) + /* The maximal number of subset can be required. */ #define MAX_SUBSET_NUM 4 |