This is the mail archive of the binutils@sourceware.org mailing list for the binutils project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[PATCH] RISC-V: Only relax to C.LUI when imm != 0 and rd != 0/2


From: Andrew Waterman <andrew@sifive.com>

This matches the ISA specification.

bfd/ChangeLog

2017-10-20  Andrew Waterman  <andrew@sifive.com>

        * elfnn-riscv.c (_bfd_riscv_relax_lui): Don't relax to c.lui
        when rd is x0.

include/ChangeLog

2017-10-20  Andrew Waterman  <andrew@sifive.com>

        * opcode/riscv.h (VALID_RVC_LUI_IMM): c.lui can't load the
        immediate 0.
---
 bfd/elfnn-riscv.c      | 5 +++--
 include/opcode/riscv.h | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c
index f7cdb4e2b0f9..0c92798d3562 100644
--- a/bfd/elfnn-riscv.c
+++ b/bfd/elfnn-riscv.c
@@ -2988,9 +2988,10 @@ _bfd_riscv_relax_lui (bfd *abfd,
       && VALID_RVC_LUI_IMM (RISCV_CONST_HIGH_PART (symval))
       && VALID_RVC_LUI_IMM (RISCV_CONST_HIGH_PART (symval + ELF_MAXPAGESIZE)))
     {
-      /* Replace LUI with C.LUI if legal (i.e., rd != x2/sp).  */
+      /* Replace LUI with C.LUI if legal (i.e., rd != x0 or x2/sp).  */
       bfd_vma lui = bfd_get_32 (abfd, contents + rel->r_offset);
-      if (((lui >> OP_SH_RD) & OP_MASK_RD) == X_SP)
+      unsigned rd = ((unsigned)lui >> OP_SH_RD) & OP_MASK_RD;
+      if (rd == 0 || rd == X_SP)
 	return TRUE;
 
       lui = (lui & (OP_MASK_RD << OP_SH_RD)) | MATCH_C_LUI;
diff --git a/include/opcode/riscv.h b/include/opcode/riscv.h
index 719565d1ba53..015e78131495 100644
--- a/include/opcode/riscv.h
+++ b/include/opcode/riscv.h
@@ -141,7 +141,7 @@ static const char * const riscv_pred_succ[16] =
 #define VALID_UTYPE_IMM(x) (EXTRACT_UTYPE_IMM(ENCODE_UTYPE_IMM(x)) == (x))
 #define VALID_UJTYPE_IMM(x) (EXTRACT_UJTYPE_IMM(ENCODE_UJTYPE_IMM(x)) == (x))
 #define VALID_RVC_IMM(x) (EXTRACT_RVC_IMM(ENCODE_RVC_IMM(x)) == (x))
-#define VALID_RVC_LUI_IMM(x) (EXTRACT_RVC_LUI_IMM(ENCODE_RVC_LUI_IMM(x)) == (x))
+#define VALID_RVC_LUI_IMM(x) (ENCODE_RVC_LUI_IMM(x) != 0 && EXTRACT_RVC_LUI_IMM(ENCODE_RVC_LUI_IMM(x)) == (x))
 #define VALID_RVC_SIMM3(x) (EXTRACT_RVC_SIMM3(ENCODE_RVC_SIMM3(x)) == (x))
 #define VALID_RVC_ADDI4SPN_IMM(x) (EXTRACT_RVC_ADDI4SPN_IMM(ENCODE_RVC_ADDI4SPN_IMM(x)) == (x))
 #define VALID_RVC_ADDI16SP_IMM(x) (EXTRACT_RVC_ADDI16SP_IMM(ENCODE_RVC_ADDI16SP_IMM(x)) == (x))
-- 
2.13.6


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]