diff options
Diffstat (limited to 'gdb/arch/x86-linux-tdesc-features.c')
| -rw-r--r-- | gdb/arch/x86-linux-tdesc-features.c | 60 |
1 files changed, 32 insertions, 28 deletions
diff --git a/gdb/arch/x86-linux-tdesc-features.c b/gdb/arch/x86-linux-tdesc-features.c index f65920c..bc34378 100644 --- a/gdb/arch/x86-linux-tdesc-features.c +++ b/gdb/arch/x86-linux-tdesc-features.c @@ -28,18 +28,21 @@ We want to cache target descriptions, and this is currently done in three separate caches, one each for i386, amd64, and x32. Additionally, - the caching we're discussing here is Linux only, and for Linux, the only - thing that has an impact on target description creation is the xcr0 - value. - - In order to ensure the cache functions correctly we need to filter out - only those xcr0 feature bits that are relevant, we can then cache target - descriptions based on the relevant feature bits. Two xcr0 values might - be different, but have the same relevant feature bits. In this case we - would expect the two xcr0 values to map to the same cache entry. */ + the caching we're discussing here is Linux only. Currently for Linux, + the only thing that has an impact on target description creation are + the supported features in xsave which are modelled by a xstate_bv + value, which has the same format than the state component bitmap. + + In order to ensure the cache functions correctly we need to filter only + those xstate_bv feature bits that are relevant, we can then cache + target descriptions based on the relevant feature bits. Two xstate_bv + values might be different, but have the same relevant feature bits. In + this case we would expect the two xstate_bv values to map to the same + cache entry. */ struct x86_xstate_feature { - /* The xstate feature mask. This is a mask against an xcr0 value. */ + /* The xstate feature mask. This is a mask against the state component + bitmap. */ uint64_t feature; /* Is this feature checked when creating an i386 target description. */ @@ -56,12 +59,13 @@ struct x86_xstate_feature { checked when building a target description for i386, amd64, or x32. If in the future, due to simplifications or refactoring, this table ever - ends up with 'true' for every xcr0 feature on every target type, then this - is an indication that this table should probably be removed, and that the - rest of the code in this file can be simplified. */ + ends up with 'true' for every xsave feature on every target type, then + this is an indication that this table should probably be removed, and + that the rest of the code in this file can be simplified. */ static constexpr x86_xstate_feature x86_linux_all_xstate_features[] = { /* Feature, i386, amd64, x32. */ + { X86_XSTATE_CET_U, false, true, true }, { X86_XSTATE_PKRU, true, true, true }, { X86_XSTATE_AVX512, true, true, true }, { X86_XSTATE_AVX, true, true, true }, @@ -73,7 +77,7 @@ static constexpr x86_xstate_feature x86_linux_all_xstate_features[] = { that are checked for when building an i386 target description. */ static constexpr uint64_t -x86_linux_i386_xcr0_feature_mask_1 () +x86_linux_i386_xstate_bv_feature_mask_1 () { uint64_t mask = 0; @@ -88,7 +92,7 @@ x86_linux_i386_xcr0_feature_mask_1 () that are checked for when building an amd64 target description. */ static constexpr uint64_t -x86_linux_amd64_xcr0_feature_mask_1 () +x86_linux_amd64_xstate_bv_feature_mask_1 () { uint64_t mask = 0; @@ -103,7 +107,7 @@ x86_linux_amd64_xcr0_feature_mask_1 () that are checked for when building an x32 target description. */ static constexpr uint64_t -x86_linux_x32_xcr0_feature_mask_1 () +x86_linux_x32_xstate_bv_feature_mask_1 () { uint64_t mask = 0; @@ -117,25 +121,25 @@ x86_linux_x32_xcr0_feature_mask_1 () /* See arch/x86-linux-tdesc-features.h. */ uint64_t -x86_linux_i386_xcr0_feature_mask () +x86_linux_i386_xstate_bv_feature_mask () { - return x86_linux_i386_xcr0_feature_mask_1 (); + return x86_linux_i386_xstate_bv_feature_mask_1 (); } /* See arch/x86-linux-tdesc-features.h. */ uint64_t -x86_linux_amd64_xcr0_feature_mask () +x86_linux_amd64_xstate_bv_feature_mask () { - return x86_linux_amd64_xcr0_feature_mask_1 (); + return x86_linux_amd64_xstate_bv_feature_mask_1 (); } /* See arch/x86-linux-tdesc-features.h. */ uint64_t -x86_linux_x32_xcr0_feature_mask () +x86_linux_x32_xstate_bv_feature_mask () { - return x86_linux_x32_xcr0_feature_mask_1 (); + return x86_linux_x32_xstate_bv_feature_mask_1 (); } #ifdef GDBSERVER @@ -143,7 +147,7 @@ x86_linux_x32_xcr0_feature_mask () /* See arch/x86-linux-tdesc-features.h. */ int -x86_linux_xcr0_to_tdesc_idx (uint64_t xcr0) +x86_linux_xstate_bv_to_tdesc_idx (uint64_t xstate_bv) { /* The following table shows which features are checked for when creating the target descriptions (see nat/x86-linux-tdesc.c), the feature order @@ -160,7 +164,7 @@ x86_linux_xcr0_to_tdesc_idx (uint64_t xcr0) for (int i = 0; i < ARRAY_SIZE (x86_linux_all_xstate_features); ++i) { - if ((xcr0 & x86_linux_all_xstate_features[i].feature) + if ((xstate_bv & x86_linux_all_xstate_features[i].feature) == x86_linux_all_xstate_features[i].feature) idx |= (1 << i); } @@ -250,17 +254,17 @@ x86_linux_i386_tdesc_count () /* See arch/x86-linux-tdesc-features.h. */ uint64_t -x86_linux_tdesc_idx_to_xcr0 (int idx) +x86_linux_tdesc_idx_to_xstate_bv (int idx) { - uint64_t xcr0 = 0; + uint64_t xstate_bv = 0; for (int i = 0; i < ARRAY_SIZE (x86_linux_all_xstate_features); ++i) { if ((idx & (1 << i)) != 0) - xcr0 |= x86_linux_all_xstate_features[i].feature; + xstate_bv |= x86_linux_all_xstate_features[i].feature; } - return xcr0; + return xstate_bv; } #endif /* IN_PROCESS_AGENT */ |