From 8e73b5763448876010aee0c6fd7f59541179d080 Mon Sep 17 00:00:00 2001 From: Iago Toral Quiroga Date: Tue, 20 Nov 2018 09:24:28 +0100 Subject: [PATCH] Revert "nir/builder: Assert that intN_t immediates fit" This reverts commit 1f29f4db1e867357a119c0c7c34fb54dc27fb682. For this to work the compiler must ensure that it never puts the values that arrive to this helper into unsigned variables at any point in its processing, since that would not apply sign extension to the value and it would break the expectations here. Unfortunately, we use uint64_t extensively to pass and copy things around, so some times we get to this helper with values that are not properly sign extended to 64-bit. Here is an example for an 8-bit value that comes from a switch case: (gdb) p /x x $1 = 0xffffffd6 The value seems to have been sign extended to 32-bit at some point getting proper sign extension, but then copied into a uint64_t which wont' apply sign extension, breaking the expectations of the assertion. Reviewed-by: Juan A. Suarez Reviewed-by: Jason Ekstrand --- src/compiler/nir/nir_builder.h | 4 ---- 1 file changed, 4 deletions(-) diff --git a/src/compiler/nir/nir_builder.h b/src/compiler/nir/nir_builder.h index e37aba23dc2..30fa1d7ec8b 100644 --- a/src/compiler/nir/nir_builder.h +++ b/src/compiler/nir/nir_builder.h @@ -330,10 +330,6 @@ nir_imm_intN_t(nir_builder *build, uint64_t x, unsigned bit_size) { nir_const_value v; - assert(bit_size == 64 || - (int64_t)x >> bit_size == 0 || - (int64_t)x >> bit_size == -1); - memset(&v, 0, sizeof(v)); assert(bit_size <= 64); v.i64[0] = x & (~0ull >> (64 - bit_size)); -- 2.30.2