With the current ASM_FUNC() macro, there is no good way to declare an alignment constraint for a function. As ASM_FUNC() switches sections, declaring the constraint before the macro invocation applies it to the current location in the previous section. Declaring the constraint after the macro invocation lets the function label point to the location prior to alignment. Depending on toolchain behaviour, this may cause the label to point to alignment padding preceding the actual function definition.
To address these issues, introduce the ASM_FUNC_ALIGN() macro, which declares the alignment constraint right before the function label. Signed-off-by: Marvin Häuser <mhaeu...@posteo.de> Cc: Leif Lindholm <quic_llind...@quicinc.com> Cc: Ard Biesheuvel <ardb+tianoc...@kernel.org> Cc: Sami Mujawar <sami.muja...@arm.com> Cc: Vitaly Cheptsov <vit9...@protonmail.com> --- ArmPkg/Include/AsmMacroIoLibV8.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/ArmPkg/Include/AsmMacroIoLibV8.h b/ArmPkg/Include/AsmMacroIoLibV8.h index 135aaeca5d0b..81164ea9c9e7 100644 --- a/ArmPkg/Include/AsmMacroIoLibV8.h +++ b/ArmPkg/Include/AsmMacroIoLibV8.h @@ -41,8 +41,19 @@ Name: ; \ AARCH64_BTI(c) +#define _ASM_FUNC_ALIGN(Name, Section, Align) \ + .global Name ; \ + .section #Section, "ax" ; \ + .type Name, %function ; \ + .balign Align ; \ + Name: ; \ + AARCH64_BTI(c) + #define ASM_FUNC(Name) _ASM_FUNC(ASM_PFX(Name), .text. ## Name) +#define ASM_FUNC_ALIGN(Name, Align) \ + _ASM_FUNC_ALIGN(ASM_PFX(Name), .text. ## Name, Align) + #define MOV32(Reg, Val) \ movz Reg, (Val) >> 16, lsl #16 ; \ movk Reg, (Val) & 0xffff -- 2.40.0 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#103311): https://edk2.groups.io/g/devel/message/103311 Mute This Topic: https://groups.io/mt/98391308/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-