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-rw-r--r--gitlab/issues_text/target_arm/host_missing/accel_TCG/2376114
1 files changed, 0 insertions, 114 deletions
diff --git a/gitlab/issues_text/target_arm/host_missing/accel_TCG/2376 b/gitlab/issues_text/target_arm/host_missing/accel_TCG/2376
deleted file mode 100644
index 9428fc045..000000000
--- a/gitlab/issues_text/target_arm/host_missing/accel_TCG/2376
+++ /dev/null
@@ -1,114 +0,0 @@
-A bug in ARM VCMLA.f16/VCMLA.f32 instructions
-Description of problem:
-The vcmla instruction performs complex-number operations on the vector registers. There is a bug in which this instruction modifies the contents of an irrelevant vector register.
-
-The reason is simple out-of-bound; the helper functions should correctly check the number of modified elements:
-```
-// target/arm/tcg/vec_helper.c
-void HELPER(gvec_fcmlah_idx)(void *vd, void *vn, void *vm, void *va,
-                             void *vfpst, uint32_t desc)
-{
-    uintptr_t opr_sz = simd_oprsz(desc);
-    float16 *d = vd, *n = vn, *m = vm, *a = va;
-    float_status *fpst = vfpst;
-    intptr_t flip = extract32(desc, SIMD_DATA_SHIFT, 1);
-    uint32_t neg_imag = extract32(desc, SIMD_DATA_SHIFT + 1, 1);
-    intptr_t index = extract32(desc, SIMD_DATA_SHIFT + 2, 2);
-    uint32_t neg_real = flip ^ neg_imag;
-    intptr_t elements = opr_sz / sizeof(float16);
-    intptr_t eltspersegment = 16 / sizeof(float16); // This should be fixed;
-    intptr_t i, j;
-
-    ...
-}
-
-...
-
-void HELPER(gvec_fcmlas_idx)(void *vd, void *vn, void *vm, void *va,
-                             void *vfpst, uint32_t desc)
-{
-    uintptr_t opr_sz = simd_oprsz(desc);
-    float32 *d = vd, *n = vn, *m = vm, *a = va;
-    float_status *fpst = vfpst;
-    intptr_t flip = extract32(desc, SIMD_DATA_SHIFT, 1);
-    uint32_t neg_imag = extract32(desc, SIMD_DATA_SHIFT + 1, 1);
-    intptr_t index = extract32(desc, SIMD_DATA_SHIFT + 2, 2);
-    uint32_t neg_real = flip ^ neg_imag;
-    intptr_t elements = opr_sz / sizeof(float32);
-    intptr_t eltspersegment = 16 / sizeof(float32); // This should be fixed;
-    intptr_t i, j;
-
-    ...
-}
-```
-Steps to reproduce:
-1. Write `test.c`.
-```
-#include <stdint.h>
-#include <stdio.h>
-#include <string.h>
-
-// zero inputs should produce zero output
-char i_D4[8] = { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };
-char i_D8[8] = { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };
-char i_D30[8] = { 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };
-char i_D31[8] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff }; // this should never be touched
-char o_D30[8];
-char o_D31[8];
-
-void __attribute__ ((noinline)) show_state() {
-    printf("D30: ");
-    for (int i = 0; i < 8; i++) {
-        printf("%02x ", o_D30[i]);
-    }
-    printf("\n");
-    printf("D31: ");
-    for (int i = 0; i < 8; i++) {
-        printf("%02x ", o_D31[i]);
-    }
-    printf("\n");
-}
-
-void __attribute__ ((noinline)) run() {
-    __asm__ (
-        "movw r7, #:lower16:i_D4\n"
-        "movt r7, #:upper16:i_D4\n"
-        "vldr d4, [r7]\n"
-        "movw r7, #:lower16:i_D8\n"
-        "movt r7, #:upper16:i_D8\n"
-        "vldr d8, [r7]\n"
-        "movw r7, #:lower16:i_D30\n"
-        "movt r7, #:upper16:i_D30\n"
-        "vldr d30, [r7]\n"
-        "movw r7, #:lower16:i_D31\n"
-        "movt r7, #:upper16:i_D31\n"
-        "vldr d31, [r7]\n"
-        "adr r7, Lbl_thumb + 1\n"
-        "bx r7\n"
-        ".thumb\n"
-        "Lbl_thumb:\n"
-        ".inst 0xfed8e804\n" // vcmla.f32       d30, d8, d4[0], #90
-        "adr r7, Lbl_arm\n"
-        "bx r7\n"
-        ".arm\n"
-        "Lbl_arm:\n"
-        "movw r7, #:lower16:o_D30\n"
-        "movt r7, #:upper16:o_D30\n"
-        "vstr d30, [r7]\n"
-        "movw r7, #:lower16:o_D31\n"
-        "movt r7, #:upper16:o_D31\n"
-        "vstr d31, [r7]\n"
-    );
-}
-
-int main(int argc, char **argv) {
-    run();
-    show_state();
-    return 0;
-}
-```
-2. Compile `test.bin` using this command: `arm-linux-gnueabihf-gcc-12 -O2 -no-pie -marm -march=armv7-a+vfpv4 ./test.c -o ./test.bin`.
-3. Run QEMU using this command: `qemu-arm -L /usr/arm-linux-gnueabihf/ ./test.bin`.
-4. The program, runs on top of the buggy QEMU, prints the value of D31 as `00 00 c0 7f 00 00 c0 7f`. It should print `ff ff ff ff ff ff ff ff` after the bug is fixed.
-Additional information:
-