arm64: Avoid breakage caused by .altmacro in fpsimd save/restore macros

Alternate macro mode is not a property of a macro definition, but a
gas runtime state that alters the way macros are expanded for ever
after (until .noaltmacro is seen).

This means that subsequent assembly code that calls other macros can
break if fpsimdmacros.h is included.

Since these instruction sequences are simple (if dull -- but in a
good way), this patch solves the problem by simply expanding the
.irp loops.  The pre-existing fpsimd_{save,restore} macros weren't
rolled with .irp anyway and the sequences affected are short, so
this change restores consistency at little cost.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/arch/arm64/include/asm/fpsimdmacros.h b/arch/arm64/include/asm/fpsimdmacros.h
index 007618b8188c0844831cd8f0255caa2bb170e09d..a2daf12930284183122bd14da5a0c2b441c91034 100644 (file)
--- a/arch/arm64/include/asm/fpsimdmacros.h
+++ b/arch/arm64/include/asm/fpsimdmacros.h
@@ -76,7 +76,6 @@
        fpsimd_restore_fpcr x\tmpnr, \state
 .endm
 
-.altmacro
 .macro fpsimd_save_partial state, numnr, tmpnr1, tmpnr2
        mrs     x\tmpnr1, fpsr
        str     w\numnr, [\state, #8]
@@ -86,11 +85,22 @@
        add     \state, \state, x\numnr, lsl #4
        sub     x\tmpnr1, x\tmpnr1, x\numnr, lsl #1
        br      x\tmpnr1
-       .irp    qa, 30, 28, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0
-       .irp    qb, %(qa + 1)
-       stp     q\qa, q\qb, [\state, # -16 * \qa - 16]
-       .endr
-       .endr
+       stp     q30, q31, [\state, #-16 * 30 - 16]
+       stp     q28, q29, [\state, #-16 * 28 - 16]
+       stp     q26, q27, [\state, #-16 * 26 - 16]
+       stp     q24, q25, [\state, #-16 * 24 - 16]
+       stp     q22, q23, [\state, #-16 * 22 - 16]
+       stp     q20, q21, [\state, #-16 * 20 - 16]
+       stp     q18, q19, [\state, #-16 * 18 - 16]
+       stp     q16, q17, [\state, #-16 * 16 - 16]
+       stp     q14, q15, [\state, #-16 * 14 - 16]
+       stp     q12, q13, [\state, #-16 * 12 - 16]
+       stp     q10, q11, [\state, #-16 * 10 - 16]
+       stp     q8, q9, [\state, #-16 * 8 - 16]
+       stp     q6, q7, [\state, #-16 * 6 - 16]
+       stp     q4, q5, [\state, #-16 * 4 - 16]
+       stp     q2, q3, [\state, #-16 * 2 - 16]
+       stp     q0, q1, [\state, #-16 * 0 - 16]
 0:
 .endm
 
@@ -103,10 +113,21 @@
        add     \state, \state, x\tmpnr2, lsl #4
        sub     x\tmpnr1, x\tmpnr1, x\tmpnr2, lsl #1
        br      x\tmpnr1
-       .irp    qa, 30, 28, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0
-       .irp    qb, %(qa + 1)
-       ldp     q\qa, q\qb, [\state, # -16 * \qa - 16]
-       .endr
-       .endr
+       ldp     q30, q31, [\state, #-16 * 30 - 16]
+       ldp     q28, q29, [\state, #-16 * 28 - 16]
+       ldp     q26, q27, [\state, #-16 * 26 - 16]
+       ldp     q24, q25, [\state, #-16 * 24 - 16]
+       ldp     q22, q23, [\state, #-16 * 22 - 16]
+       ldp     q20, q21, [\state, #-16 * 20 - 16]
+       ldp     q18, q19, [\state, #-16 * 18 - 16]
+       ldp     q16, q17, [\state, #-16 * 16 - 16]
+       ldp     q14, q15, [\state, #-16 * 14 - 16]
+       ldp     q12, q13, [\state, #-16 * 12 - 16]
+       ldp     q10, q11, [\state, #-16 * 10 - 16]
+       ldp     q8, q9, [\state, #-16 * 8 - 16]
+       ldp     q6, q7, [\state, #-16 * 6 - 16]
+       ldp     q4, q5, [\state, #-16 * 4 - 16]
+       ldp     q2, q3, [\state, #-16 * 2 - 16]
+       ldp     q0, q1, [\state, #-16 * 0 - 16]
 0:
 .endm