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| author | Nelson Chu <nelson.chu@sifive.com> | 2021-11-29 04:48:20 -0800 |
|---|---|---|
| committer | Kito Cheng <kito.cheng@sifive.com> | 2021-12-06 10:55:01 +0800 |
| commit | 45116f342057b7facecd3d05c2091ce3a77eda59 (patch) | |
| tree | c4ec4f8c446d5fe5d59d4259f41e44f07c8eaa25 /libgcc/config/riscv | |
| parent | b880d1514c1e3dd75a6ea311a5cc956742bd713c (diff) | |
| download | gcc-45116f342057b7facecd3d05c2091ce3a77eda59.zip gcc-45116f342057b7facecd3d05c2091ce3a77eda59.tar.gz gcc-45116f342057b7facecd3d05c2091ce3a77eda59.tar.bz2 | |
RISC-V: jal cannot refer to a default visibility symbol for shared object.
This is the original binutils bugzilla report,
https://sourceware.org/bugzilla/show_bug.cgi?id=28509
And this is the first version of the proposed binutils patch,
https://sourceware.org/pipermail/binutils/2021-November/118398.html
After applying the binutils patch, I get the the unexpected error when
building libgcc,
/scratch/nelsonc/riscv-gnu-toolchain/riscv-gcc/libgcc/config/riscv/div.S:42:
/scratch/nelsonc/build-upstream/rv64gc-linux/build-install/riscv64-unknown-linux-gnu/bin/ld: relocation R_RISCV_JAL against `__udivdi3' which may bind externally can not be used when making a shared object; recompile with -fPIC
Therefore, this patch add an extra hidden alias symbol for __udivdi3, and
then use HIDDEN_JUMPTARGET to target a non-preemptible symbol instead.
The solution is similar to glibc as follows,
https://sourceware.org/git/?p=glibc.git;a=commit;h=68389203832ab39dd0dbaabbc4059e7fff51c29b
libgcc/ChangeLog:
* config/riscv/div.S: Add the hidden alias symbol for __udivdi3, and
then use HIDDEN_JUMPTARGET to target it since it is non-preemptible.
* config/riscv/riscv-asm.h: Added new macros HIDDEN_JUMPTARGET and
HIDDEN_DEF.
Diffstat (limited to 'libgcc/config/riscv')
| -rw-r--r-- | libgcc/config/riscv/div.S | 15 | ||||
| -rw-r--r-- | libgcc/config/riscv/riscv-asm.h | 6 |
2 files changed, 14 insertions, 7 deletions
diff --git a/libgcc/config/riscv/div.S b/libgcc/config/riscv/div.S index c9bd787..723c3b8 100644 --- a/libgcc/config/riscv/div.S +++ b/libgcc/config/riscv/div.S @@ -40,7 +40,7 @@ FUNC_BEGIN (__udivsi3) sll a0, a0, 32 sll a1, a1, 32 move t0, ra - jal __udivdi3 + jal HIDDEN_JUMPTARGET(__udivdi3) sext.w a0, a0 jr t0 FUNC_END (__udivsi3) @@ -52,7 +52,7 @@ FUNC_BEGIN (__umodsi3) srl a0, a0, 32 srl a1, a1, 32 move t0, ra - jal __udivdi3 + jal HIDDEN_JUMPTARGET(__udivdi3) sext.w a0, a1 jr t0 FUNC_END (__umodsi3) @@ -95,11 +95,12 @@ FUNC_BEGIN (__udivdi3) .L5: ret FUNC_END (__udivdi3) +HIDDEN_DEF (__udivdi3) FUNC_BEGIN (__umoddi3) /* Call __udivdi3(a0, a1), then return the remainder, which is in a1. */ move t0, ra - jal __udivdi3 + jal HIDDEN_JUMPTARGET(__udivdi3) move a0, a1 jr t0 FUNC_END (__umoddi3) @@ -111,12 +112,12 @@ FUNC_END (__umoddi3) bgtz a1, .L12 /* Compute __udivdi3(-a0, a1), then negate the result. */ neg a1, a1 - j __udivdi3 /* Compute __udivdi3(-a0, -a1). */ + j HIDDEN_JUMPTARGET(__udivdi3) /* Compute __udivdi3(-a0, -a1). */ .L11: /* Compute __udivdi3(a0, -a1), then negate the result. */ neg a1, a1 .L12: move t0, ra - jal __udivdi3 + jal HIDDEN_JUMPTARGET(__udivdi3) neg a0, a0 jr t0 FUNC_END (__divdi3) @@ -126,7 +127,7 @@ FUNC_BEGIN (__moddi3) bltz a1, .L31 bltz a0, .L32 .L30: - jal __udivdi3 /* The dividend is not negative. */ + jal HIDDEN_JUMPTARGET(__udivdi3) /* The dividend is not negative. */ move a0, a1 jr t0 .L31: @@ -134,7 +135,7 @@ FUNC_BEGIN (__moddi3) bgez a0, .L30 .L32: neg a0, a0 - jal __udivdi3 /* The dividend is hella negative. */ + jal HIDDEN_JUMPTARGET(__udivdi3) /* The dividend is hella negative. */ neg a0, a1 jr t0 FUNC_END (__moddi3) diff --git a/libgcc/config/riscv/riscv-asm.h b/libgcc/config/riscv/riscv-asm.h index 8550707..96dd85b 100644 --- a/libgcc/config/riscv/riscv-asm.h +++ b/libgcc/config/riscv/riscv-asm.h @@ -33,3 +33,9 @@ X: #define FUNC_ALIAS(X,Y) \ .globl X; \ X = Y + +#define CONCAT1(a, b) CONCAT2(a, b) +#define CONCAT2(a, b) a ## b +#define HIDDEN_JUMPTARGET(X) CONCAT1(__hidden_, X) +#define HIDDEN_DEF(X) FUNC_ALIAS(HIDDEN_JUMPTARGET(X), X); \ + .hidden HIDDEN_JUMPTARGET(X) |