diff options
Diffstat (limited to 'compiler/GHC/CmmToAsm/X86/CodeGen.hs')
| -rw-r--r-- | compiler/GHC/CmmToAsm/X86/CodeGen.hs | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/compiler/GHC/CmmToAsm/X86/CodeGen.hs b/compiler/GHC/CmmToAsm/X86/CodeGen.hs index d3902dad84..34f907b4f2 100644 --- a/compiler/GHC/CmmToAsm/X86/CodeGen.hs +++ b/compiler/GHC/CmmToAsm/X86/CodeGen.hs @@ -1158,6 +1158,22 @@ getRegister' _ is32Bit (CmmLit (CmmInt 0 width)) in return (Any format code) +-- Handle symbol references with LEA and %rip-relative addressing. +-- See Note [%rip-relative addressing on x86-64]. +getRegister' platform is32Bit (CmmLit lit) + | is_label lit + , not is32Bit + = do let format = cmmTypeFormat (cmmLitType platform lit) + imm = litToImm lit + op = OpAddr (AddrBaseIndex EABaseRip EAIndexNone imm) + code dst = unitOL (LEA format op (OpReg dst)) + return (Any format code) + where + is_label (CmmLabel {}) = True + is_label (CmmLabelOff {}) = True + is_label (CmmLabelDiffOff {}) = True + is_label _ = False + -- optimisation for loading small literals on x86_64: take advantage -- of the automatic zero-extension from 32 to 64 bits, because the 32-bit -- instruction forms are shorter. |