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| author | Jack Carter <jack.carter@imgtec.com> | 2013-03-22 00:29:10 +0000 |
|---|---|---|
| committer | Jack Carter <jack.carter@imgtec.com> | 2013-03-22 00:29:10 +0000 |
| commit | 4f69a0f25df15231d78c9ce5de735d7529c8bde0 (patch) | |
| tree | 650cbe8c6cd4eae2085b81c38693627dce62d410 | |
| parent | 96efb4a4425ebe24c783da1af6c6ae05d80ae887 (diff) | |
| download | bcm5719-llvm-4f69a0f25df15231d78c9ce5de735d7529c8bde0.tar.gz bcm5719-llvm-4f69a0f25df15231d78c9ce5de735d7529c8bde0.zip | |
Fix the invalid opcode for Mips branch instructions in the assembler
For mips a branch an 18-bit signed offset (the 16-bit
offset field shifted left 2 bits) is added to the
address of the instruction following the branch
(not the branch itself), in the branch delay slot,
to form a PC-relative effective target address.
Previously, the code generator did not perform the
shift of the immediate branch offset which resulted
in wrong instruction opcode. This patch fixes the issue.
Contributor: Vladimir Medic
llvm-svn: 177687
| -rw-r--r-- | llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp | 10 | ||||
| -rw-r--r-- | llvm/test/MC/Mips/mips-jump-instructions.s | 24 |
2 files changed, 18 insertions, 16 deletions
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp index 96f93a07898..e198a7c983f 100644 --- a/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp +++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsMCCodeEmitter.cpp @@ -160,8 +160,9 @@ getBranchTargetOpValue(const MCInst &MI, unsigned OpNo, const MCOperand &MO = MI.getOperand(OpNo); - // If the destination is an immediate, we have nothing to do. - if (MO.isImm()) return MO.getImm(); + // If the destination is an immediate, divide by 4. + if (MO.isImm()) return MO.getImm() >> 2; + assert(MO.isExpr() && "getBranchTargetOpValue expects only expressions or immediates"); @@ -179,8 +180,9 @@ getJumpTargetOpValue(const MCInst &MI, unsigned OpNo, SmallVectorImpl<MCFixup> &Fixups) const { const MCOperand &MO = MI.getOperand(OpNo); - // If the destination is an immediate, we have nothing to do. - if (MO.isImm()) return MO.getImm(); + // If the destination is an immediate, divide by 4. + if (MO.isImm()) return MO.getImm()>>2; + assert(MO.isExpr() && "getJumpTargetOpValue expects only expressions or an immediate"); diff --git a/llvm/test/MC/Mips/mips-jump-instructions.s b/llvm/test/MC/Mips/mips-jump-instructions.s index bc2d7203981..849eae93250 100644 --- a/llvm/test/MC/Mips/mips-jump-instructions.s +++ b/llvm/test/MC/Mips/mips-jump-instructions.s @@ -5,25 +5,25 @@ #------------------------------------------------------------------------------ # Branch instructions #------------------------------------------------------------------------------ -# CHECK: b 1332 # encoding: [0x34,0x05,0x00,0x10] +# CHECK: b 1332 # encoding: [0x4d,0x01,0x00,0x10] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: bc1f 1332 # encoding: [0x34,0x05,0x00,0x45] +# CHECK: bc1f 1332 # encoding: [0x4d,0x01,0x00,0x45] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: bc1t 1332 # encoding: [0x34,0x05,0x01,0x45] +# CHECK: bc1t 1332 # encoding: [0x4d,0x01,0x01,0x45] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: beq $9, $6, 1332 # encoding: [0x34,0x05,0x26,0x11] +# CHECK: beq $9, $6, 1332 # encoding: [0x4d,0x01,0x26,0x11] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: bgez $6, 1332 # encoding: [0x34,0x05,0xc1,0x04] +# CHECK: bgez $6, 1332 # encoding: [0x4d,0x01,0xc1,0x04] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: bgezal $6, 1332 # encoding: [0x34,0x05,0xd1,0x04] +# CHECK: bgezal $6, 1332 # encoding: [0x4d,0x01,0xd1,0x04] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: bgtz $6, 1332 # encoding: [0x34,0x05,0xc0,0x1c] +# CHECK: bgtz $6, 1332 # encoding: [0x4d,0x01,0xc0,0x1c] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: blez $6, 1332 # encoding: [0x34,0x05,0xc0,0x18] +# CHECK: blez $6, 1332 # encoding: [0x4d,0x01,0xc0,0x18] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: bne $9, $6, 1332 # encoding: [0x34,0x05,0x26,0x15] +# CHECK: bne $9, $6, 1332 # encoding: [0x4d,0x01,0x26,0x15] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: bal 1332 # encoding: [0x34,0x05,0x11,0x04] +# CHECK: bal 1332 # encoding: [0x4d,0x01,0x11,0x04] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] b 1332 nop @@ -50,9 +50,9 @@ end_of_code: #------------------------------------------------------------------------------ # Jump instructions #------------------------------------------------------------------------------ -# CHECK: j 1328 # encoding: [0x30,0x05,0x00,0x08] +# CHECK: j 1328 # encoding: [0x4c,0x01,0x00,0x08] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] -# CHECK: jal 1328 # encoding: [0x30,0x05,0x00,0x0c] +# CHECK: jal 1328 # encoding: [0x4c,0x01,0x00,0x0c] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] # CHECK: jalr $6 # encoding: [0x09,0xf8,0xc0,0x00] # CHECK: nop # encoding: [0x00,0x00,0x00,0x00] |
