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| author | Carter Sande <carter.sande@duodecima.technology> | 2019-06-24 22:32:50 -0700 |
|---|---|---|
| committer | Carter Sande <carter.sande@duodecima.technology> | 2019-06-24 22:32:50 -0700 |
| commit | cd02630da82b6b0a59583160b12c286a7aec7f8c (patch) | |
| tree | f3bfbcfc37aac71290e98e364361e9454134c271 /std | |
| parent | de2b0cd722ca8fe98d16c86825db4cb2a70931c6 (diff) | |
| download | zig-cd02630da82b6b0a59583160b12c286a7aec7f8c.tar.gz zig-cd02630da82b6b0a59583160b12c286a7aec7f8c.zip | |
compiler-rt: Support thumb versions older than armv6
Add versions of __aeabi_memset and __aeabi_memclr which do not use mov
instructions between low registers, as this is unsupported on thumbv4t
and thumbv5.
Diffstat (limited to 'std')
| -rw-r--r-- | std/special/compiler_rt.zig | 43 |
1 files changed, 41 insertions, 2 deletions
diff --git a/std/special/compiler_rt.zig b/std/special/compiler_rt.zig index 46607a3adf..95867d6952 100644 --- a/std/special/compiler_rt.zig +++ b/std/special/compiler_rt.zig @@ -471,6 +471,28 @@ test "usesThumb1" { //etc. } +const use_thumb_1_pre_armv6 = usesThumb1PreArmv6(builtin.arch); + +fn usesThumb1PreArmv6(arch: builtin.Arch) bool { + return switch (arch) { + .thumb => switch (arch.thumb) { + .v5, + .v5te, + .v4t, + => true, + else => false, + }, + .thumbeb => switch (arch.thumbeb) { + .v5, + .v5te, + .v4t, + => true, + else => false, + }, + else => false, + }; +} + nakedcc fn __aeabi_memcpy() noreturn { @setRuntimeSafety(false); if (use_thumb_1) { @@ -505,7 +527,16 @@ nakedcc fn __aeabi_memmove() noreturn { nakedcc fn __aeabi_memset() noreturn { @setRuntimeSafety(false); - if (use_thumb_1) { + if (use_thumb_1_pre_armv6) { + asm volatile ( + \\ eors r1, r2 + \\ eors r2, r1 + \\ eors r1, r2 + \\ push {r7, lr} + \\ b memset + \\ pop {r7, pc} + ); + } else if (use_thumb_1) { asm volatile ( \\ mov r3, r1 \\ mov r1, r2 @@ -527,7 +558,15 @@ nakedcc fn __aeabi_memset() noreturn { nakedcc fn __aeabi_memclr() noreturn { @setRuntimeSafety(false); - if (use_thumb_1) { + if (use_thumb_1_pre_armv6) { + asm volatile ( + \\ adds r2, r1, #0 + \\ movs r1, #0 + \\ push {r7, lr} + \\ bl memset + \\ pop {r7, pc} + ); + } else if (use_thumb_1) { asm volatile ( \\ mov r2, r1 \\ movs r1, #0 |